First of all, to take game at range requires practice. If you think you're going to go out and just smack a deer in the vitals at 800 yards on the first round you are mistaken. You need whatever rifle you choose to be in a round that will be able to afford you plenty of practice from many positions. The chance you will find yourself in a perfect prone position with a rear support is slim to non while hunting. At the least you will need to practice shooting off a tripod and shooting off things such as logs, rocks, tree branches or whatever you may find in the area you will be hunting to get you high enough to take a shot.
Now that we're past that, obviously the first choice you have to make when planning a hunting rifle is game. Deer, got that. If you plan on using it for other large game, now is the time to think about that. Next you need to choose a chambering with an acceptable bullet for hunting that is going to provide enough velocity at the maximum intended range to allow the bullet to expand, and enou energy to allow adequate penetration. As a general rule of thumb most bullets work well at 1800FPS and some will open up with slightly less velocity. For medium size deer you want no less than 800ft lbs of energy, ideally more towards 900ft lbs.
Match bullets are very accurate but some are unpredictable on game. The ones that I have found to perform consistently on deer sized game and put them down would be the Hornady Amax, Lapua Scenar, and Nosler Custom Competition. Berger also has a line of hunting VLD's that work great but I have not used any of their other bullets on game. I plan on taking some deer with the Juggernaut this year to see how they do.
With your choice of 30-06 it is going to be just marginal for what you want to do if it works well at all. One of the first calipers I'd look at is the 6.5's. Running the numbers the 260 and 6.5 creed will both keep the high BC bullets going enough to do what you need to do at a maximum range of 800 yards. 6.5 SAUM would also be a very good choice and the barrel life is reported to be just as good as the others with the right powder. 7mm SAUM would be another good choice as would 7mm rem mag. All of these rifles will be tame in a reasonable weight rifle with no muzzle break, the 6.5's more so. This is another reason why I would not recommend the 30-06 or any of the 30 cal magnums in the weight rifle you seem to want to go with, with the bullets you will need to run the recoil will be on the stiff side.
I would weigh out the plus's and minus's of the 260, 6.5 creed, 6.5 SAUM, 7 SAUM, and 7 Rem Mag. They obviously have pros and cons such as recoil and brass availability. The 6.5 SAUM you are also going to have to find a builder with the reamer (GAP has it) and you are going to have to custom dies made. Not a big deal but something to think about. The two 7mm's are obviously going to have more recoil and barrel life isn't as definitive. You can probably run H1000 in them too though just like the 6.5 SAUM since the burn rate is right and get at least somewhat comparable barrel life.
Then decide the end weight and setup you want and go from there. You said you don't want a 15lbs rifle, well what are you looking at with scope and all? 10lbs? 12lbs? This is going to be a major factor in the components you choose specifically barrel contour. You'll probably end up around a #4, #5 or rem varmint and you can flute it to save a few ounces. The barrel length you need for the round you choose will also play a part.
For stock I would keep it simple with something like a McMillan HTG, A3 Sporter, Manner MCS-T, etc. Stay away from the chassis if you don't want to end up with a pig of a rifle. You'll also need to decide of you want a simple floor plate bottom metal or a magazine. If you go with a magazine I would recommend against one with a protruding latch, it WILL get hung up on your clothing or pack while walking around, I guarantee it. Something like the APA is what I would recommend because the mag release is built in with the trigger guard.
For action I would personally recommend a custom but stay away from the big bulky overbuilt ones, they mean weight. Stiller, Pierce, and Defiance all make great actions as do others. Stiller is probably the most readily available, they're always in stock somewhere to ship out as soon as payment is made. Bugholes, a hide member always has a bunch in stock too. Any of these actions will be super smooth and have all the features. If you have these features done to a R700 action as well as trueing you will spend just as much. For example Bugholes sells Stillers with a base and pinned recoil lug for $975. That Remington you're looking at that doesn't have nearly the upgrade will run your $800 by time you get a good base and a recoil lug, for $175 more you get a custom action with more features and options such as straight or curved bolt handle, and magazine cut.
Keep your optics in mind too if you're keeping weight down. Obviously a 30oz scope may not be reasonable, but it may. I would also keep the rings aluminum or NF Ultralights to save weight.
The only other advice I'd give is to keep the trigger around 3.5-4lbs so you can feel it in the cold and stay away from triggers that are prone to failure such as jewel.
Hope this helps, good luck with your build.
