Green’s Dictionary of Slang

mashkin-shop n.

a pawnbroker’s.

1887		Bulletin (Sydney) 15 Oct. 13/1: Amorous actor confined to his room next day, and owing to impecuniosity has to arrange with friend to visit the ‘motshkin shop’ to raise funds for the purchase of a new set of grinders.
1899		A. Binstead Houndsditch Day by Day 187: Hobinstock’s was the only mashkin-shop that had taken its shutters down.