Re: Rear sprocket bracket?
I'd contact Pirate Cycles and ask. I know for a fact that many members here use that same sprocket adapter on various bikes, not just coaster brake bikes.
The critical element is the diameter of your rear hub. That adapter you linked to must fit the hub precisely and that requires careful measurment by the buyer.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"