Is this the bass you're talking about?
http://www.jayturser.com/jtb-134.php
If so, that sure looks like a metal bridge to me.
Regardless - DON'T DO IT!!! Considering the fact that it's a semi-hollow body, you're just asking for trouble. Drilling into the top & having a standard Fender-type bridge will put all sorts of tension on the top of the bass.
Basses similiar to this (such as a Hofner) have bridges such as these for a reason.
If you like the tone of your bass currently & were just planning on switching strictly for cosmetic purposes, I would reconsider.
My .02, of course...
