It seems like the only thing keeping you from rebuilding one would be the friction surface, the springs and the plastic bushings. I would bet you could come up with the springs and bushings with a little research. Bushing could probably be made easy enough as well. Then comes the question of resurfacing. I have been told you can't resurface a DMF, is that just because the two halves move making it impossible to hold or is there another reason? If it is disassembled, I would guess you could true up the surface by placing it on the friction surface. Might require a jig of some sort but I haven't seen the inside of one of these yet. Luckily, I think mine is good. It just had a clutch job fairly recently before I tore it down and the moron who did it put the disk in upside down... even though it is clearly marked "this side to flywheel". 
