Re: BSA Scope on AR's
If you need something just to get you by on a .22 rimfire, try something like a lower end bushnell, a leupold rifleman series, or one of Cabela's budget scopes. Also look into things like Hawke, low-end vortex, sightmark, etc.
BTW- SWFA has a nikon prostaff 3-9 on clearance for $99, would be great for a .22 rimfire or other small cal rifles.
For the AR you might want something a bit better, but things like that cheap Nikon would probably "suffice". I personally have run these on ARs and been fine:
Nikon (buckmaster series)
Burris (fullfield series)
Vortex (viper series)
Falcon (menace series)
There are others as well, just buy from a reputable company... and through a reputable dealer (like one of our hide vendors) who will back you up if you have problems.