I need to have the breaker mounted in a case of some sort.

If you go the local contractor supplier they may carry Scepter NEMA rated enclosures, the small ones run from $9.00.
Google Scepter enclosures.
Max.

 

You can buy IP45 rated terminal boxes of various sizes which have receiver holes for mounting DIN rail inside.

If you go the local contractor supplier they may carry Scepter NEMA rated enclosures

Thanks guys. Incredibly helpful.

Looks like I have a project to build