Thanks for all the interest in, and appreciation of this story. It's encouraging that no-one has called me a madman, or idiot. Yet.
Ventura
Your comment about Scandalli confirms my fears...
I thought that the curved array of treble switches - which to me looks worryingly like a 'BEFORE' photo in an orthodontist's adverisement - came before the straight array of switches, and after the 'typewriter key' pattern, so quite early on. I'm guessing that this box dates from the 50s: is this about right?
In spite of your warning about the faux ivory finish, I attacked the already-damaged treble switch. I ended up - with considerable trepidation- having to remove more of its surface than I expected, to get rid of the yellow-brown staining. Simple polishing wasn't enough. Luckily, the veining pattern could be seen on the back of the switch, indicating that it is full-thickness. The result is excellent, with preservation of the subtle veining, much better matching the white piano keys. The important thing was to avoid overheating the material, so no power tools. The plastic appears to be polystyrene, which makes life easier, because it's so easy to solvent-weld. The damaged switch was cracked near the pivot hole, so the cover and metalwork were separated, and the crack filled and reinforced behind and out of sight with MEK and polystyrene - standard plastic modeller technique.... Only 12 more to go...
The treble pallets are going to require some thinking about. I'm not sure whether I should try to maintain originality as much as possible - and the alloy pallets are sort of appealing - or take your advice and change the pallets. I'm hoping someone will come along and tell me how to re-do the fixing in the original, or near-original manner. But then, I suppose genuine improvements are allowed... I don't fancy having to bend the key rods much though.
Regarding my daughter's "little devious and generous heart". Yes, a wonderful heart, but more devious than I had suspected, and aided and abetted by her mother. They both kept the secret in the face of my several times lamenting the missed opportunity of saving this box. I wonder what else they're keeping from me?
noelekal
Thanks for the 'bin lid' link. I suspect these are the same that appear on Parrot boxes. They can probably be made to fit, but it would require some head-scratching, and might even be easier to make lids from scratch. Neither option is very attractive...
Ffingers
Thank you for what sounds like a potentially very generous offer of help. I'll certainly PM you in due course. But I'm worried that you seem to be condemming your box to death or dismantling - can't it be saved?