Nope, most of the pads mentioned here can fit on a stock T50RP - indeed most of the mods don't change the outward appearance at all. Some can be pretty hard to put on though...
Oh also, uh. It seems that the baffle is kind of coming loose on my pair. I think it's because I filled it completely with plasticine, even where the little connector box was supposed to go, and it eventually put too much pressure on it and it kind of snapped. A little piece of plastic fell out last time I opened it.
...I hope I can fix this with superglue? It doesn't seem to affect the sound at all though, which is good...