I'm new and need some help.

Hi im new here and i need some help. I have just bought a B18C5 ITR motor and tranny. It also came with a dc sports headre instead of the factory one. I got it really really cheap because the guy had no clue what he had, he was a friend of mine, and the block has a crack in it but everything else is fine. Anybody have ne suggestions on where to find a new block or is any one selling one thanks