I can do most things on an AR that doesn't require actual machining (that includes drilling new gas ports, and the holes for front sight taper pins). Dimpling a barrel for a gas block 90% of the time, cleaning up a gas port, pinning and welding sure.
Just screwing on two flash hiders with crush washers or shims? Not pinning and welding? After removing the pinned and welded ones there previously?
This,
http://www.centurionarms.com/product-p/0609-cc.htm rail system?
I should be able to do all that for like $65 assuming nothing weird is going on with what needs to come off.
(Chester from I5 Guns in Lacey/Olympia). Advanced certification from SAW for the M16/M4 series.