Where is the happening place to buy slant parts

I got an nos MP one from eBay for my build. Also have a brand new/built probably 30+to cloyes double roller set around here somewhere.
I heard good things about something called "IWIS"(something like that) chain which I saw the MP chain marked with that so I went with that one. Mine's in a truck though. Probably won't see 4k rpm very much...