In that situation with a pair of the same model, I would swop the parts and make up a decent gun. i would then put the other one in the 'To Do' pile to be refurbished later. This would be carried out either as a 'Cabinet Queen ' or a functioning user depending on the rarity.
I will put up with a lot, tatty, rusty guns don't bother me, but they must function as the makers intended or better. I can't stand to see a gun not working.