First, a good used PCM shouldn't run more than $50-$100 depending on what code you need/find. You could try posting a WTB in the appropriate section, just be sure to mention year and tranny.
Honestly though, PCM's rarely fail. I'd be willing to bet that something happened with all the work you've done that is the true source of your no-start. Presuming you're now getting fuel, spark, and air as you mentioned in your other post, I suspect you may not have the timing belt on properly. I have seen this on several occasions where the car won't start despite everything seeming fine, and eventually found the timing belt off by a few teeth.
I recommend pulling the timing covers and triple-checking timing belt alignment again, to the point of removing it and re-installing it to make sure all the marks line up properly. People have inadvertently put the timing belt on backwards on more than one occasion, or lined up the marks incorrectly.
