Places like Macs and other antique auto parts stores might carry a reproduction one. There are also people who specialize in finding special parts if you want an original one, but they don't tend to be cheap. You could also try hunting through make or model specific flea markets. There is also eBay and Craig's list. Junk yards are also a possibility. In other words, there are many possibilities, you just have to keep your eyes open and look around.
Welcome to these forums, and stick around, you might like it here.
Maybe one of the mods can help you out by moving this to the classic cars section, not that it really makes a difference, but for formality.