You might want to see if some sort of a velcro restraint system would work for you. I know they don't offer the same type of restraint that metal cuffs would, but at least your hands wouldn't slip out. Same goes for just buying rope and getting tied up instead of cuffed.

As for sexy clothing, there have to be a few stores out there that cater to smaller women, wouldn't you think? (I'm assuming you are female, and I apologize if you aren't.) Perhaps you could try out some of the paint-on latex for a good time? Otherwise, you could see if you have a friend who can sew and would be willing to make sexy clothes for you (or, if you are talented, make your own).