I'm pretty sure there is not serial numbers on pumps. Here's what you can do click on "PARTS" top of this page then find the year and model of your ski, click on Propulsion External, this will bring up a diagram of the pump, enter 1 on the corresponding part number and click add to cart, this will bring up the part number.
Once you get the part number, just google the part number, it should give you corresponding skis.
Most 90's models ski's use the same size pump, it varies in construction, plastic, aluminum or bronze.
ok thanks for replying. i appreciate the help using the parts schematic located on this site, i will use it often in the future.
as for the cross reference that wouldnt help right now as i was given a jet pump assmbly from another ski to possibly use on my boat.. the one that i currently have on the port side the "dog ears" on the pump assmbly where it bolts to the hull are thicker then the stock one on my starboard side and it barely bolts up,, when i took the boat for a run the wear ring slid back about 1/2 inch.. i am going to be taking pics and posting here today as i remove the assembly to repair.