We just finished our 52 pick up and we looked high and low for clutch head bolts. While a few are available from the vendors mentioned above, they are limited to things like the rear fender to box bolts, and that's about it. We did finally find a supplier that had many more to offer, but you need to measure the old ones you have, and then order them in quantities needed. The good thing is that you can order just the quatity you need. They have a web site
www.restorationspecialties.com and it really helped us find almost all that we needed. Suggest you order their catalogue first and go from there.