is there any cheap rstb like the fstb that are on ebay?

 

Yes... not as common, but it exists...

Let me also just say that a RSTB on the Max doesn't do a whole lot but kill some trunk space, so your money might be better spent elsewhere... like a RSB for example, that is a single mod, which according to many people, makes a huge difference in handling....

See this thread from yesterday....

http://forums.maxima.org/showthread.php?t=358357