Curl--
My buddy just bought an 03 carbine that was found rolled up in a carpet in a repo'd house in Missouri, apparently had been there for decades. Not pristine like yours, but a nice clean using rifle. We loaded up some downrated loads with Norma 204, and it shoots like a dream! With your bore size, I think you'll be fine loading the Hornady .264 RN and letting the undersized bullet slug itself up, as discussed in a prior post. Have fun with it, and fear not--this rifle wants to be fired!

Malcolm