[Arran]

 No stain, toned or tinted lacquer was used, if the bottom was black, and not extra dark walnut tone spary, then black lacquer paint will be fine. I should point out something though, there is tinted lacquer and there is toner, tinted lacquer is what you want on the veneer and that frame around the picture tube, toner is more opaque. Before any of that goes on the grain will need to be filled with a filler, especially if it is mahogany which is very open grained, although you would still need to do so with walnut veneer as well. The original finish was top coated with gloss lacquer that was then rubbed out after being allowed to cure for a certain length of time. I don't know what species of veneer these sets used but it does look like a mahogany, scape the finish off one of the old pieces and wet it to see what the grain and colour is like, if in doubt photograph it and post it here.
Regards
Arran