Master cylinder cover/gasket

I'm not aware of anyplace that sells just the MC cap. You could try a local auto parts store in the "Help" products section for the gasket maybe.

Also, you could take your MC cap to the local parts store and see if they can match it up w/ a rebuilt unit. Don't use the MC, but you could just use the cap and gasket.

This one looks like yours:

http://www.autopartswarehouse.com/search/?N=10177+1607+4294964488+9182

Same one that's on my Demon and same part # for 72 Cuda