Thanks. The manufacturer of the receiver offered to sell me a few, but I was kind of hoping to be able to put bit better part in to prevent this down the road.
As for what happened, not a clue. Powered it up, big pop, the smell of n-type in the air... After I get my hands on a few more of these I'll be able to see what kind of damage (hopefully nothing) the amplifier stage took, but everything looked OK...