How did you determine that it is a 239?
There is no crate engine Y-Block, as most people are familiar with the term, at this time. That's not to say that there are not people who can build an engine and ship it to you but you will not be mail ordering it from Summit, or Jegs, etc, and it is going to be a custom build, rather than something off the shelf. If you want quality these are the people to contact, Ted Eaton, www.eatonbalancing.com, Tim McMaster, www.yblockguy.com, John Mummert, www.ford-y-block.com.
There are places that you can get a remanufactured engine, but these are high volume shops where attention to detail is not top priority.
Also, do not discredit local machine shops. The key with any local shop, if they do not already know Ys is that they are willing, with your help, to take some time and do a little homework. If they are not willing to do that then you do not want them building a Y.
Lawrenceville, GA