Jere,  you are in better shape than I was when refinishing my
niece's player -- we didn't even have the block of wood!  The
springs should be available from Player-Care, as well as some
buttons, which you will have to modify to fit your piano, as the
case fronts are different widths and thickness.

You will also have to figure out how to keep the buttons from
lifting out of the case.  This could be as simple as a large
leather nut (bigger than the hole in the wood) on the end of the
button shaft that pushes down on the spring to open the tube.

David Dewey
Oroville, California