I was sitting on an older 110 in 7mm and was in the same boat - what to do with it. I eventually decided to go big and found a 30" .338 Edge barrel from McGowen to use. And like you I though I could probably do the work myself, but not having the necessary tools I thought it would simply be easier to take to my gunsmith. Plus, I bought a muzzlebrake and had him install that when he was done.
The .300RUM brass has been relatively easy to find, H1000 hasn't been too awful to find, and 300g Bergers seem to pop up often enough that I haven't had any downtime trying to find load components.
Go big or go home!!
This would make your 800-1000 yard goal relatively easy to achieve.