another Question, are you in an area that is/may be pushing Non-Lead (LFP) Monolithics? The 1:8 is great then, because the "Standard weight" LFPs are the same length and bearing distance of the heavier Cup and Core bullets. I.E. the 55g Barnes Varmint Grenade specify right on the box a 1:10 twist or faster, and they shoot like crap out of my 1:12 22-250. May as well use the 870 with Dead Coyote for the groups I get at 100 yds.
As for who's barrel, I would go with whoever is making a pre-fit for the 22cm that fits your action from the prefered companies on the Hide and contact them about chambering in 22-250. I would love to do this, but with a Sako, Howa, and 2 Mausers I am going to have to get a blank and have it fit and chambered by my trusted local gunsmith.