I wouldn't trust Ebay for something so large - espeically if it's labeled JDM. You can't really tell if it's JDM just by looking at it and EVERYTHING on ebay is JDM these days so they think they can sell it for more than normal.
agent is right, check out the junk yards first. You may even try getting with some of the guys out here that have done the auto/manual conversion to see if they'll hook you up with their old tranny. Also, post a WTB in the FS section of the forum - someone may be able to help you out.
Finally, PM vtecfed. He's got a junk yard hookup and he may be able to get you what you need.
hih and welcome to HAN