what type of bass shakers are they?
any vintage amp will work fine.. i have CrowsonTech tes-100 tactile transducers (couch shakers) and have an old kenwood amp and preamp running about 250 watts to each one.
it works really well, but it all depends on your shaker's specs. some are cheap and cant handle that much power. I dont think id spend any extra hooking them up if they werent the crowson tech's or the buttkickers. Those are the only 2 ive seen that are quality. The crowsontech's being the more quality of the two IMO.
check them out at crowsontech.com. i recommend the shakers but not the amp, its a little too weak to power them. ive tried a few different amps, but for some reason the vintage ones seem to work better, unless you want to spend a lot of money.