Call Great Lakes Skipper. They have this Centurion ski pylon holder in stock. Ask them to grab it and then ask them if they have any pylons that will fit in that holder. I'm assuming that you have the 2.5 inch holder in your bilge?
Centurion Pylon Holder
Here's one that's 2 and 3/8ths. You might have to get creative with your mounting in the floor. I think you can find what you need to make it all work. I've seen used ones come up for sale including on this board. Get good at eBay searching for them too.
gekko pylon available