[BattleRifleG3]

You sure it's a model 111 and not a 11 in 308? I thought the three digit numbers indicated long action and the 2 digit ones short. If you look at most listings, they will say long or short action, detachable or internal mag. I think what fits the 10FP will fit the 11. Check out www.savagearms.com, they have a list of their nomenclature that will help you understand what those letters mean.
Concerning barrels, I don't know of any replacement barrels out there, but Savage offers heavy barreled 308 rifles. Probably the reason you won't find extra barrels, cause they make them themselves and sell them at good prices.

I think you can buy a new Savage with the sniper stock and heavy barrel. Not sure which calibers though. Check out their website.

 

[BattleRifleG3]

Sounds like a good idea, as long as you're happy with what you're getting. That way someone else is also happy with your old rifle. You'll probably spend less upgrading than trying to install new parts, as smiths tend to charge a bit for such major work.

 

[BattleRifleG3]

Just to check, is the 20" barrel your preference? Because a 26" barrel is the same price. I tend to prefer bigger, since you'll get a little more velocity and the greater weight will reduce recoil.

But 20" has its advantages, and from what I understand, it's no less accurate.

 

[BattleRifleG3]

I'm fond of the G3 action myself. Good luck with the PTR, let us know how it goes.