Welcome to the club!
I was tempted to do a repair with fiberglass mat and JB weld but I take this car long distances over the road and I'd really rather not have to fork out the big bucks for an unexpected repair at a dealership far from home when I can take care of it now in a controlled environment.
BTW, shop around a little, radiators can be had for much less than $400. Mine will be less than $250.