they are not that expensive, expect an upcharge of 70-175 dollars on new ones and no price difference when buying used (which I prefer anyway).
a refinish will cost you a lot more and the chance of finding a nice grain under the original finish is minimal not to mention some manufacturers has used bodies made of up to 5 pieces in the past on their opaque finished instruments, alder or basswood bodies which don't make up for good looking natural finish wood as ash does and last but not least - you could find there is a lot of filler in the body so you stripped a good finish only to find out you cant refinish the bass in natural anyway.