As far as I know, the last one's were downtown at Mermaids or possibly at Treasure Island.
On just this one particular slot game, profited close to 100k over the years on these PIES
There were quite a few $5 machines around in the late 90's.........................you mentioned Primm Rail, back in the day, 12 miles away in the town of Jean it was much better, as they had no less than 10 $5 and $1 pies and other +EV slots varieties and very few huslters, some days would make two or three trips there daily. As far as PIES, Treasure Island and Jean were probably the top two venues for me personally in regard to just PIES