+ 1 for the realoading!!!! You would be amazed at how well a tuned factory gun will shoot.
This is obviously not going to be a bench gun, so I see no need to buy an aftermarket action. You have the best factory action on the planet, and once trued up by a GOOD gunsmith, it will shoot with any custom action on the planet. You may not be able to shoot as fast as you could with a fancy multi-port custom, which, IMO is CRITICAL in 1K benchrest. But, for your needs, who cares about speed. You want accuracy!!! And besides, if you look at the 1000 yard equipment lists, if it's not a custom action, IT'S A REMMINGTON!!! Ok, I admit, Savage is comming on strong lately, but , the remmy is still KING!!
Also, have it bedded by the same GOOD smith. Even if it already has an aluminum bedding block, have him skim-bed it. Have the smith work or replace the trigger, if needed.
Now.........you still think you want it to shoot better............have a new tube put on it.....BY THE SAME GOOD SMITH!!!!
Again, I agree with Ron about learning to handload. Use the same methods as a BR shooter. Good equipmet, good measuring tools, case prep, ect......
But as far as buying a new action.........save your cash!!!
JMO, of course....
Good Luck,
Tod