You're in a good 1HZ groove right now. Praise away!
Mine came with the rig so not totally sure of it's origin. Looks pretty identical to the Ebay ones I see posted there tho. It's held up for the 6+ years I've had it and seems repairable.
I'm thinking about pulling mine and handing it off to these guys to R&R while the 77 is off the (salted) roads for the winter
Maine Radiator MFG.
Maine Radiator produces high quality, heavy duty radiator cores and tanks for industrial, high performance, antique vehicles and equipment as well as custom designs for any application.

They did a 40 radiator for me a lifetime ago that is still solid