RE: WHAT IS THE BEST CALIBER....
If you are looking for cheaper priced and more readily available ammo then I'd go with the 308. The 22-250 and 204 arent ideal for deer sized game hunting. I love the WSM's but the ammo does cost more and has less selection then was you'll find with the 308.
The same can prob be said for the 243 also. THat would be my 2nd choice in your situation.