Good luck trying to trace it's lineage. You are basically forced to go backwards, which usually ends up in a broken chain where it was sold at a gun show, etc... Unfortunately, there's not much option other than taking your chances with it.
If the lower is tight will ALL uppers, it's one of the ones that needed to be fitted. We can usually modify them to fit easier if you want to send it to us.
As to refinishing, I can only do the aluminum parts at present, and the price would be $35 per piece, but I recommend the teflon for best finish, which is $30 per piece, in addition to the hardcoat.