Dual exhaust on an early 273

We're going to put dual exhaust on my 64 Valiant which has a 273 with stock exhaust manifolds.

Does anyone make after martket dual exhaust kits?

Does anyone offer only head pipes? Then we could get past the fire wall and fabricate the rest.

Does anyone offer a single exhaust setup at a reasonable price? The we could cut up the front portion and go from there.

Is there another way to approach this that we haven't thought of?