a pop
Per item, as of the cost of something. At $3 a pop, these decorations are a steal.
— a pop
costing a specified amount per item. North American informal 1999 Tim Lott White City Blue I never thought I'd see the day when a curry house would do Margaritas. The waiter looks delighted. I'm not surprised at six pounds a pop.
a pop
Slang Apiece; each: Tickets to the benefit were $100 a pop.