gauges aren't working

So we have a 2000 Supra Launch and none of the gauges are working. After searching around online it seems like when this happens it is because the MDC-1600 sending unit isn't working anymore. I call up the local Supra dealer and they want $442 for the part. Naturally I look around to find it cheaper. Well I found it from a mastercraft dealer for $245 shipped, http://www.bakesonline.com/detail.aspx?ID=1381 has it for $265, and Tommy's says $350ish. The problem is the lady at Tommy's is saying that the malibu one only works on malibus, the supra one on supras etc.... Does anyone know if this is true or not. Bakes says that the one they have works on malibus but has also been know to work on other manufacturers. They also keep telling me they need the 11 digit number off the one in the boat. It will probably be this weekend before we can get up to storage and take the old one out so I won't have those numbers until then. Thanks for any help you guys can provide!