[DanEC]

I think Brent would be a very good and accessible source for a new clutch. I have McLeod clutches in two cars including my ERA and have no problems with them. I prefer diaphragm clutches. That's what most people run. I believe the disc on a 12 inch clutch measures 11.5 inches. Those 12 inch McLeod clutches on the posted link, depending on the transmission input you're using, are probably what you need. Again Brent would be a good source for advice.

Since you are this far into it the smart thing would be to have the flywheel surfaced. At minimum, clean up the surface with emery cloth to remove any glaze and check it with a straightedge and even a dial indicator mounted to the block. It's not easy to find information of what acceptable run out is on a mounted flywheel because a portion of it could be in the crank flange and even if there is a bit of run out in the surface, with the pressure plate mounted to it some say it doesn't really matter except in severe cases. I did find a MOPAR spec once of .005 in max run out for the flywheel.