Wondering what your opinions are for this. Seller claims it is a 320 pair with International Vending Company perforations, but ONLY between the stamps--the edges show no evidence of perforation:
http://www.ebay.com/itm/SCOTT-320-v...AOSwxg5XxavL According to Belasco's book on Vending and Affixing stamps, International Vending perforations were added only one row at a time...so I suppose this result is theoretically possible. But I've never seen that. Add to that the really late usage (1936) and I assume this is an altered 320 pair without real Vending perforations. Thoughts?
https://i.ebayimg.com/images/g/eKIA.../s-l1600.jpg