I want to replace a couple of slughtered keyboards

Hello!
I need a simple interfacing method for two of my client computers and one to the server computer. Today we use slaughtered keyboards for this and it works fine mostly but sometimes one or two connected buttons loose contact and this occur at the "keyboard-cable junction". I don't want to spend more money on simboards and buy simboards for for all three computers.

I need this arrangement to be able to change whats displayed on the PMRJ ND screen - VOR, FIX, NDB, ARPRT etc. In this setup the Capt and FO ND displays are partially separated from each other and it gives a feel of having two separate systems, eg the Capt side might show airports and VORs on the ND display while on the FO side NDBs are shown.

I'd like to remove the slughtered keyboards and I need something else for interfacing. Something more stable!
Is Hagstroem keyboards a solution??
Any other possible solution??

Regards

Per Alm