This is what I ended up doing. I used a 1/2" PVC saddle connector, along with a 1/2" threaded connector and a soft plastic furniture leg, inserted into that for the bottom. I tried to come up with a way to keep from modifying the seat permanently, but I just couldn't keep the legs from sliding out, so I screwed them to the seat. Also, I went ahead and trimmed back most of the saddle, so I just had basically a peg, with a curved, cradle top.
Now, I've already posted this on the Passport FB group, and there's some nay-sayers stating Hobie folks told them the seat latch was meant to pop out and the feet I made, will hurt the deck. My feet are BARELY touching the deck when you are sitting in the seat, so the load is carried along the side rails, just as before, however, if you scoot forward and begin a lever action, the feet kick in to prevent the latch from popping up. I think this will be fine, as I'm only in that position long enough to get in my fish bag cooler on the bow, or stow my mirage drive in the bow section.
https://photos.app.goo.gl/Z4vUpaEosKzZK6uy5