Mounting & Coupling motors with Encoders 2

Need a mechanical designer, perhaps a machine shop that is good at this type of work. I would like CAD drawing of the entire module. The goal of this project is to have the flippers (as shown in first picture), controlled by: a) Bigger stronger motors - for which a suggested one is shown in the second picture. It is a cordless drill motor (Harbor Freight $20). This likely will work. However if you have another solution fo a low cost DC motor that is strong I will consider that. b) The new motors must be strongly coupled to the shafts of the flippers. I have 2 coupling pieces that will fit the drill motors - however this also is only a suggestion. and I am not sure how you would do that coupling. c) Alternatively you can suggest another way entirely to "flip" the flippers. But not much time to be spent on this unless you have an easy solution. d) The motors also need encoders on them. Hopefully you know what those are. And I am looking for between 500 and 1000 counts per half rev of the flippers. If you can get the encoders before the gearing of the motors and return many more counts, even better (do not make a huge undertaking though). Best Regards, Steve