Thrift find - Karl Wilkes 'History Lesson #5' limited edition #10/200

I found this today at a thrift store today. I looked the artist Karl Wilkes & the print History Lesson #5 up and saw it is selling for over $2,000!

But it said the print was 30" x 40" and when I measured mine it is 26" x 30" inside edge of frame to inside edge of frame including the black & the visible art itself is only 26.5" x 18.5"?

Mine says it is #10 of a 200 edition which is the same as what it says on the different websites I found it. But they also say Masterpiece Edition?
Was there a different - smaller - edition besides Masterpiece Edition that was also a limited edition?

Could mine be a copy/print someone made? (the edition # looks good as does the signature)

Ant help would be appreciated; I'm not sure what I have & don't want to try to sell it until I know.
Thank you

 

https://www.k-bid.com/auction/1513/item/51 same frame and size.

 

Signed and numbered reproduction

 

Big difference!

 

Holy crap it sold for $11.50? I paid twice that at a thrift store($24.95)!!

 

Perhaps it didn't 'matter' as much in 2014

Doesn't look like a particularly great auction house either, damaged frame also

Just because that one sold for that, doesn't mean you can't make a profit on yours