you would come off a lot better buying a used low mileage tranny. No one builds them better than Honda.....and our old resident Gil, a tranny expert by trade, would probably tell you the same thing. First get a diagnosis, and report your findings here. I recently replaced my engine and tranny for right at $4,000 for a 50k set. 
This was including labor, and miscellaneous parts and such. The tranny cost me about $800...and you can find some for less...but like I said, let us know.
This was including labor, and miscellaneous parts and such. The tranny cost me about $800...and you can find some for less...but like I said, let us know.