Hahaha Hahaha Sounds like a 5p blank got mixed up with the 10ps and was struck as such. You're probably looking at £5-10. That sound a bit optimistic. Ebay seems to get very under excited about errors. Can you be optimistic with a price of £5? While I agree that I personally wouldn't pay £5-10 for this type of error, you'd still struggle to find a similar example for less..