Mills Bell Not Sure of Type

[ACMech]

My uncle found out I was fixing up Vintage Pachinkos and asked me if I wanted an old nickel slot machine he had that wasn't working. I of course said yes, and the pic below is what I got. Needless to say, I'm very happy. The innards were coated with WD-40, and it was all very sticky. However, the real problem was that the escalator (the part that takes the nickels across the top) had an opening in it and was dropping nickels into the mechanism, where one of them had gotten stuck in the payout mechanism, forcing a 3 coin payout each time it was played. I've got it all working now, and it's working perfectly, however, it still needs a lot of TLC to get it in good shape. I know it's a Mills Bell, I'm not sure of the year, or how to find it out, some things that don't match the book I got were: it doesn't have a plunger to slow down the big lever you pull to get it to start, and the rod the wheels are on has a screw that holds it in on each end. Incidentally, the jackpot works, as my wife was playing with it and got it to pay out , which I understand is one of the things that sometimes doesn't work. I however, after playing it multiple times (hours) haven't been able to get a jackpot... If anybody knows something about this particular style of machine, or could tell me how to date it, that would be neat info for me to find out.

Thanks!
Mills Bell.jpg