There are two people I know that do that work.
Try Paul Drabik at Wannapinball. I used to work with him (although not on pinball machines). Great person and well known.
Also, Rich Corbo works on the games at Morristown Game Vault. Lots of pinsiders have used him in NJ. https://pinside.com/pinball/forum/topic/rich-corbo-awesome-nj-tech