What are my seats worth?

[LS Blazer]

I have decided not to use the original seats in my build...I know you purists will be mad at me, but since I'm going to drive it every day, I thought shoulder belts would be a good idea.
I have the original wide, metal backed buckets out of the front and the original rear seat from my 1972 K5 CST that have been reupholstered and have not been used since(I think all of the brackets are there, as well). I have had a buddy express some interest in buying them, but he is insistent that I name the price. I want to be fair to both sides. What are they worth?

I also have a chrome glove box door that he wants. If anyone has any ideas on it, I would appreciate that, too.

Thanks!