Sticking piston in brake caliper

I have a sticking piston in a brake caliper, sliding bolts and springs are OK.

It can be depressed but is not releasing properly.

Is it feasible to remove and clean it up or is it a hiding to nothing, new calipers are only about £50.

And if I do replace, will I have to do the pair?

Cheers,

Rick

You can but I've never had good results and always had to do them again and/or replace the caliper.