Robert, the Ithaca 37 triggers don't even come close to qualifying as a target grade trigger. I've had them since I was a kid and never heard of anyone making a release for them. They just aren't considered a target gun. At best you might get someone to slick one up and make a target grade pull trigger out of one.
If you want one bad enough I'm sure you can find someone that will do it. I made a release trigger for a Mossberg, because everyone said it couldn't be done, and a friend wanted one. I don't have a mod 37 trigger to look at, but if I can find one I'll see what I can come up with.