RE: most accurate factory .22
Right off hand I would say the Kimber is extremely accurate, but pricey as you already know. The kimber is an a grown man's 22, not a kid's 22. Meaning that for $600+, it is for serious shooting. I have an old Savage M19 NRA Match that I bought about 10 years ago at a flea market, that 1/2" groups all day long with match ammo, but go to heck with CCI maxi mags and Rem. yellow jackets. Anyway that's another story.
I would look at at the heavy barreled Ruger 10/22. A buddy of mine has one that he put a 2.5-10x44 Simmons Aetec on, and that thing is scary accurate, even out to 100yds. My 10/22 sporter is not quite that accurate but with a 4x I can get about 3/4" groups at 50yds, a little better on good days and a little worse on bad days. I am thinking very hard about getting a Houge combination heavy barrel and stock for my 10/22.