Is there a VW part for the coolant tank cap?

[Shawn Stanford]

Let me be completely honest here: I'm not a purist. I buy my cars to drive them and I really don't care if the part says Porsche or VW or even Ford if it keeps the car on the road. I've put a ton of VW parts into my Cayenne over the years, usually at about 1/3 to 1/2 the price of an equivalent Porsche part. My 928 has a Chevy alternator (a much better part than the original Bosch/Rhone), and a Passat blower motor.

Early coolant caps are $25, which isn't a lot of money, but seems like a stupid amount of money for a part that costs $5 if it's for a VW.

Does anyone know of a VW (or whatever) coolant cap for first gen cars?

Thanks.