If the dealer hadn't had the OEM part in stock, I would've tried an automotive equivalent. Somewhere else on the forum, I read about the transient protection of the OEM relay due to the Rocket's high current requirements. At the very least, I'm going to figure out a cross-reference list incase another one goes tits up on a road trip.
The brain trust here was incredibly helpful in getting it sorted out. When I rode a Suzuki, there was a similar forum that, once upon a time, had similarly experienced old salts. But, after a few years, the whole forum just turned into a non-stop slap fight over religion and politics.