Originally Posted by
Dannihilator
The spacing won't be right and a 7/8 speed chain won't fit in a 9 speed deraillieur.
False, 9 speed XTR RD works is working great with 8 speed XTR cassette and a sachs 8 speed chain along with a 7 speed XT thumbie adjusted to shift eight.
To the OP, Deore DX will work fine for your application, XT quality but a little heavier and dirt cheap on ebay.