Help identifying these pistons

I should have taken pictures of the rest of the pistons. They all have a small valve relief cut into the top but this one looks like the valve hit it, the rest of them are not mushroomed out. I don't think there is an F on the top, that is the decimal point. They were in a motor he used for drag racing. Are they worth anything or worth using? I will try load more pictures of the other pistons and the rods tomorrow, I only have these pictures on my phone right now. I'm trying to decide if I should use them to build a street motor or if I should sell them and look for something different.

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