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Thursday 28 December 2017 at 22:22
Found what I'm very sure is the exact same game via Worthpoint - https://www.worthpoint.com/worthopedia/1967-midway-monster-gun-rifle-419012034
The P1 credit button is a dead giveaway.
A few photos I've found have different colors on the base, around the backglass, and the rifle counter top. Mine is...
Source: http://pinside.com/pinball/forum/topic/1967-midway-monster-gun-repair-and-restoration#post-4146602