What are these worth?

[HoH]

Hi All,

I am not very familiar with banger parts, but I got a bunch with a car I bought a while ago. The car is gone, so I don't need the parts, but the previous owner told me they are really rare and worth some decent money. Here are the first couple parts, a pair of heads. One is aluminum, the other is cast iron and needs a little cleanup. Take a look at the pics and let me know what you think I can realistically get for them.

Thanks,
John T