To summarize what I found and close out this thread.
The female connector is made by Delphi/Aptiv and is part number 12162017 and apparently was used by GM back in the 80s and early 90s for air conditioner compressors and used by some heavy trucks and, for whatever reason, is used by whoever makes the fuel pump that Rotax uses. The additional locking part for this connector is number 12124824.
I contacted Aptiv and asked the part number for the mating male connector and their reply was that they don’t sell that part. I then tried the same with Mouser and chatted with a technical rep there and he said that the mating part is a “manufacturer built-in” part and Aptiv only provides the drawings for that part (which I found), but it is up to the equipment manufacturer to build the male mating connector into their part, as was done with GM air conditioner compressors and the Rotax fuel pump. I assume Rotax had to pay someone to make a mating loose connector so they could sell their 881304 connector kit. This likely explains why it costs so much.
FYI, as of today at Mouser, the female connector side can be had for less than $15 for all of the parts assuming you buy the high end silver plated terminals which cost $1.30 or so each. With standard terminals that cost 50 cents each, the total cost for a connector is under $10.
It appears there are only two options:
1. Pay $150+ for the Rotax kit with four connectors and pins or
2. Cut off the connectors from the factory harness and use those on the fuel pumps and then splice wire in between.