The motor isn't worth more than any other pre-'86 4-port 13B, and generally less than a TII engine. But it's a good ported 13B, so you could probably get some good dough for it.
As for the dual DCD setup, well, it's not worth anything at all. They suck and no one wants them. You'd better send it to me so I can... er, properly dispose of it for you.
Seriously, though, yeah, they're pretty desirable.