Navman Push Buttons

[Pelikaan]

I have a Navman Trackfish 6600 plotter in the cockpit to navigate by. My pushbutten pad doesn’t function much anymore, but the rest of the unit works perfectly well. Navman no longer exists, Northstar who made a virtually identical unit no longer exists and Navionics, the new owner cannot or will not provide spares, saying they have none.
I have 3 options:
 Replace the Navman
 Find an old Navman 6600 with a function pad to replace mine
 Try fixing the pushbutton pad by buying standard pushbutton pads and make it somehow work.
Has anyone had similar problems and what solutions were found (apart from throwing the unit out and buying a new one?

Hopefully someone can help.

Cheers

Hans
SV Pelikaan