I too shoot mostly colour slide film and I personally like Duggal - http://www.duggal.com/ and have brought my 4x5 transparency film to them.
Now they're not the chatty types so if you're looking for that kind of service, you're not going to get it there. I know some APUGers look for this sort of thing. I don't and can't stand yappy behind the counter people.
Hmmm ... but they're not in Tribeca. Shoot nevermind. I guess this was a chatty post!