A PS2 Sega Saturn pad I bought a few years ago, eventually had sticky-feeling worn out membranes, especially in the D-pad area. I tried replacing them with the membranes from an American model 1 Saturn pad, but the button membranes ended up being too tight a fit and I could barely bush buttons. The D-pad membrane just barely fit and was usable for a good while after I broke it in. Would the membranes from a official model 2 pad be a perfect fit, or am i completely fucked and have to drop another hundred bucks on another PS2 Saturn pad?
I don't know if this information is still helpful to you after over 2 months, but I can confirm that the rubber parts of a model 2 Saturn pad fit into the PS2 controller just fine (except for the select/start button, of course).