Epoxy will work fine, the JB marine stuff has worked well for me.

I've welded steel pans in the car before- just pull the valve covers first, learned the valve cover trick from a friend of mine, he ripped open the milodon pan on his 440 with a speed bump and it was his driver so he needed a quick fix so he welded it in the car, he ignited the oil fumes in the pan and blew out both breathers and bulged the valley pan against the manifold. When I say blew out the breathers 1 was 80' away and the other was MIA, that was 12 years ago and it still has the bulged valley pan- it makes a good conversation piece.