Hyper pak exhaust manifold value

I’m wondering if the factory hyper pak exhaust manifolds ever come up for sale and what price they go for. I stopped by an old friends house and he has a set of them on a 170, I’m assuming was a factory hyper pak engine.

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That is freaky!! The set I have I got from the second owner in 1972. The rear manifold was cut and welded in almost the exact place. I was told it was to clear the steering on a 32 Stude Hobby Stock roundy round car. That being said, they don't come up often and sell right away. A set came up on epay a couple of years ago and sold dirt cheap in a matter of minutes. They are not being reproduced, yet. There is a set down in Oz with the intent to see about reproducing them. The same company that bought the rights and molds to make the dutra dual manifolds. Here is my rear manifold.
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