OXPEX 1964 Woodstock on PB36 1960 Wrapper

Those of a certain age will remember a little music concert called Woodstock. I am sure though that the 1964 Oxford Philatelic Society Annual Banquet and Exhibition at Woodstock, Ontario in Canada was a much bigger event. This was an advertising piece for Jack's Stamp Farm and printed on what appears to be a 1960 Canada Post wrapper with the Unitrade number PB36.