Between those two prices and weighing how good of a friend they are and what you would do with them should you not sell any I think you can come up with something fair.
Honestly though, unless you have very few seeds or your friends wants a lot of them I would just give them away. Or just charge shipping if you have to mail them.
Note: I just want to point out to anyone wondering about the big price difference between FTS and the ICPS that the seeds from the ICPS are donated so they don't have any over head other than storing them. FTS seeds come from their breeding program so they put a lot of work into getting those seeds. Plus with FTS you know you're getting seeds that are quite genetically diverse. With the ICPS you don't know, they could be from some awesome cross, or they could be from someones huge collection of typicals.