Ionian Islands NC 7-11 Pairs...real Or Fake? Please Help.

I found these today while dealing with an auction lot I purchased several months ago. They were on a blank Scott page in clear mounts. They were identified as NC 7-11 for Ionian Islands (looked right by my catalogue), at a cat. value of 3400. That seems too good to be true. I usually don't find much. They are still in the mounts, and glue looks intact on the back. Anyway, any ideas out there?

Amy

A real N11 sell around $ 150 , anyway, your's overprint don't match; look on the photo, if I draw a line from the I to the midle of the S, notice the distance from the line of the M in mili... and look at the I in isole . lool at the "e" not same font