Looks like a lot of caked on grease. I'd disassemble it and clean it up to get a better idea of where you are at. Check www.pinrepair.com/em if you haven't taken one of these units apart before (http://www.pinrepair.com/em/index2.htm#steps).

Basically every time you score a particular point value (probably 1 point) the match unit increments. It has no "home" position and just goes around and around. It is wired up so that if your score (usually the 10s digit) matches the position of the unit at the end of game, you win a free game.

You could ask on https://pinside.com/pinball/forum/topic/the-em-seeking-parts-thread or check ebay for a replacement. But clean it up first, it may be fine.