Mark IV,
You are correct in that you can find some at that price typically for Chevys and or non-swivel, and even then the cheap Mr. Gasket swivels are @ a 45deg, and not at a 90deg req for the BDR.
I've really only seen ones around this price range and above in this particular design.
JEGS Performance Products 53090: Small Block Ford Swivel Thermostat Housing 1-1/2" Hose Connection | JEGS
Please link the ones you've found as I'd like to purchase one. Looking for anodized Black.