On the page I linked in the OP, there are measurements of the (ridiculously expensive) replacement fan. That is identical to the one on the card.
The one you linked, while a bit smaller (75mm instead of 85mm), would probably fit on the card. If I don't find anything better, I'll probably buy it. For $4 including shipping there is not much risk.
Two options, replace the whole cooler with a aftermarket one, ArticCooling, Akasa, Thermalright etc, or cut one more blade of the fan, so the balance is even on the even. I will try the second option first, because it is already broken and you loose nothing for a try.
Unfortunately, since I broke off the first blade, I broke off many others. I didn't even think I could "fix" it by breaking off another blade.
Thanks for the quick responses.