Ive seen the holster below for sale recently and it was advertised as a Bulgarian Luger holster. I would imagine that one way to rule a Luger in or out would be to look at the top of the magazine pouch to see if it has a crescent cut out to accomodate the base of a Luger magazine. If it's straight across then it probably wasn't originally for a Luger. Others here will know better than me.
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