I’ll recommend some modern keyboards that are suitable for your retrokit - I’m a big fan of Unicomp keyboards myself, though they do not do N-key rollover, if that is something important to you. Their lighter shade (they call it ‘white’) is more of a grey than a beige.

You may also consider USB keyboards that can handle P/S2 protocol with use of an adapter (not all of them can do this very well). I have a WASD keyboard for my modern PC that I sometimes also use with my older machines. I would recommend them, but they appear to be out of business.