Luso technically and commercially supports the Veetronix range of switches:

Luso is the sole European distributor for Veetronix switches, the preferred choice for professional audio and broadcast applications.

Being magnetically actuated, no moving parts touch the switch contact. The switches are hermetically sealed which prevents air, oil or other contaminants from attacking the contacts. These two features explain why these switches have a long lifetime and failures are unheard of. Veetronix also offers a custom marking service for their wide range of keycaps.