Looking for HP 9810A keyboard springs

[Camiel Vanderhoeven]

Hi Guys,

I've got an HP 9810A that has been stored in sub-optimal conditions by
a previous owner; a lot of the keyboard springs have rusted away, so
I'm looking for a replacement. These are about 15.5mm outer diameter,
0.35mm thick wire, about 10mm high when uncompressed, and have only
about 1.5 turns of wire.

Any pointers would be appreciated!

Camiel.