Trying to get back on topic - to answer the OPs actual question, why not give StewMac or All Parts a call, describe the bass you have (and have the hole spacing measurements available for your current bridge), and what you are trying to accomplish. I am 100% certain that one of those 2 fine companies will be able to help you out for under $30 USD... Probably better advice than you've been getting here (myself included, sorry about that.) Best of luck to ya! I have a 5 string 19mm original Sadowsky bridge that I would lend you, but a 5'r wont help out on a 4 string...