Shifter Replacement for vintage cross bike?
 

The 7-speed shifter/brake combo unit on my 1994 Raleigh CT400 flat-bar cross bike is failing, and it will likely need to be replaced soon if cleaning it thoroughly with solvent doesn't solve the "not shifting" problem. It is part of the Shimano 400CX group (shifter is p/n ST-C040) which I think was a solid mid-range group at the time. The bike is in mint condition and definitely a keeper.

In case I need to replace one or both of the shifters (these are very hard to find) , what should I be looking to buy that would be comparable in performance or possibly better, and that will work with the rest of the 400CX parts?

New 7 speed shifters are still being made in rapidfire plus, twist, and thumbshifters.

These early shifters did break often from usage but they didnt break spontaneously from storage so if they're gummed up from old grease, some solvent should free them up