any b-series motor should fit in ur dx. check out
www.hasport.com for parts and more info. you might need different mounts, wireing, axles, shift linkage, ecu an stuff like that.
my uncle did a b18c swap (JDM) on his 96 dx 4 door, and it was a pain in the ass, but wow it was worth it. the hardest thing about the swap is the wireing.