That petcock looks similar to that used on my friend's CL350 that's in my shop ATM. local Honda (or even Suzuki for that OEM-like fit) dealer may have what you need. Otherwise, you could look into valves from Pingle. I can't think of any other fuel valve makers off the top of my head, that's all I've ever heard of people using outside of OEM.
As for your filler, I have no idea...maybe ebay? Various vintage Harley aftermarket companies?