This might or might not be part of what he was after, but the O.P. might want to consider, if he hasn't made his choice, whether an "upgraded" clutch is really desirable.
When I was a lot younger, I put roadster clutches in my 510 wagons, but why? I never raced them. But I had read that the roadster clutch was "better," and didn't think it out. My engines were rebuilt to be a bit more efficient, and made a bit more power, but the factory clutch would still have been fine. The factory clutch worked fine for anyone who wasn't into "street performance" (again why would one want a street performance station wagon?}. Different strokes, I guess, but today there's a real good reason to avoid racier clutches and their stronger springs, and that is the endless traffic-crawls one must endure in our over-populated country. O.P., do you really want to constantly modulate a high-pressure clutch pedal while in a herd of cars stopping and starting for miles at a time?