The original coin counters supplied with commercial coin-op arcade games are designed not to be reset. It's so route operators can keep their employees honest or in the event of a machine break-in simple math and the previous weeks' meter reading can provide you with an exact amount of money stolen.
Every coin counting meter manufacturer makes a resetable version of what you have in there now. Just copy all the infor off the existing meter like manufacturer, model number, voltage, type of mounting, etc. and visit the manufacturer's website. I'm sure if you contact the manufacturer's tech support dept they'd be happy to tell you what resetable model crosses to what you have now. Resetable meters cost about 10 bucks.