It's actually 64-66 metallic beige and I'm pretty sure I got it from Jim Carters truck parts online. The charcoal grey is my own concoction of grey and black Van Sickle tractor paint that I mixed up to match the old paint in my interior.
The beige was a premixed paint that needs no hardener or catalyst. But I found that when I added hardener it gave it more gloss and made the paint harder. So you can do that if you like the glossier look. The original probably wasn't very glossy.
Darren