One problem I had was with the gaskets for the Concert Grand reproducer, since they are not being made anymore. Fortunately I found that regular Columbia gaskets worked as well, you only had to double them up to make them thicker.
Lucky that I found the correct black and gold peacock horn on eBay.

I decided to use red turntable felt, I think it fits better to the black and gold horn than the usual green. I don't know what the original color would have been, just thought red looks quite Royal.

Before: After: