Car cassette radio: Clarion 4RX5370R - buttons not...

Question

The front panel is removable.

Some of the navigation buttons have stopped working due to age. I took the panel off and have operated the buttons directly on the board, and the same ones still don't work. Replacing the buttons looks possible but tricky. Easier would be getting another front panel replacement. Can't seem to find it though.
Otherwise it is working fine, so don't need to replace the entire system.

Can you help please?
Thanks
Stephen Clarke
[e-mail]