I need help to evaluate a Ukraine exile sheet 1959

[reibne0]

Hey

Recently i get across a huge collection of stamps and i m doing researches about them before reselling.

But a unique sheet of Ukraine 1959 konotop stamp i can't find it in any catalog also i can't find similar one in internet.

I already have offer of 100$ from a freind , but I'm little confused .

Any information will be helpful.

 

[waxu_93]

Possibly a stamp fabricated by the government-in-exile，never be used by any postoffice.