Said I would update when I had stuff in hand, so here we go...
The thunderjet (t-jet) reproduction hubs I bought for buttons all look good. The ones from ebay seller HO Reproductions are - according to the Trek sites mentioned earlier in this thread - the most accurate. The other ones I bought from modelmho.com look fine, too - I actually prefer them for this model because the back is flat instead of having a nub, so it will sit flush to the surface of the screen panel more easily.
The watch crowns have turned out to be a pain in the posterior. The ones that are most readily available are WAY too small, and it's much easier to find yellow gold than silver-toned. The originals must have been somthing uncommon, as they are like 5mm in diameter - most stone watch crowns are around 3mm. I have spent weeks trying to get some on ebay to no avail, and the local watch repair places that carry parts all have ones that are too small. I found one online resource for 5mm stone crowns, but they only come in black.
So the search continues. In the meantime, I plan to buy the Radio Shack 3/32" phono jacks and stick a jewel on top!
Thanks again to all who contributed info to this thread.
Rick