Bad ESN, anything I can do?

Bought a bad ESN phone off of craigslist, phone looks brand new and no other problems besides that, I've gone through all the menu's and everything and no problems except I cant activate it. Is it possible to buy a broken phone off of ebay and swap out the parts from the working phone? Like just swap the part that holds the ESN if that makes any sense?

I did not know that the phone had a bad ESN when I bought it, and I cant get a hold of the seller. I don't have his actual email only the craigslist one and we met at a 7-11. So anything that I could do to get this phone functional and not lose all of the money would be great.