just grab another TCU from a 90-95 Accord in the junkyard. I've never seen one go bad, but I'm sure it can and will happen. Just don't pay much. <$20, or walk. Those things are very common, and are not rare to find, so they are hard to sell. Good for you, bad for them.
There are also solenoids on the front of the tranny, and a couple of sensors that I would trade out before junking the tranny. They are held on by 10 mm bolts, and have Oring gaskets, making them a snap to swap. I had a spare tranny, but I gave it away, sorry.