[Katsunami]

Maybe this will be of some help. I've bought two short stories by Terry Brooks. They're background stories in the world of Shannara.

Allanon's Quest -> 34 pages @ 2400 characters per page
The Weapons Master's Choice -> 42 pages @ 2400 characters per page.

They cost US $0.99 (€0.75) a piece at Diesel Ebooks, and €0.91 a piece at Kobo. That's 2.39 eurocents a page, maximum, for a story of a best selling author, and these stories are longer than yours combined. I know, you can't really make a price based on th number of pages, but if someone like Terry Brooks asks €0.99 for a 42-page story, I wouldn't have the nerve to ask that price for a 5-8 page story as an amateur writer. You'd be asking just short of $4 for 24 pages, while one could also get a 400 page novel at that price, with a little shopping around.

If it were me, I'd not (dare to) ask more than €0.60 (US $0.79) for the lot of them.