25-06 is great, but since you want to stay light short action may be the way to go. I would go with .260 to satisfy the between .243 and 30-06 requirement. But if you want to be on the edge you could try the 25 WSSM. Looks like it would meet you needs well, but your not going to find ammo at the counter store, and in my opinion probly never will. Just don't see it catching on.

I like the mod. 70 featherweight. The 25 WSSM only weighs 6 lbs. There long actions weight 1.25 lbs more.

The REM 700 mnt. comes in .260 weights 6.5 lbs.

Another good choose budget pending is the Sako finnlight their 25.06 weights 6.5 lbs. I have a 75 hunter in 7mm-08 (very sweet) opps. just read you didn't want to spend sako money.