I know that in the USA most of the machines were original ones, but here in Chile the complete opposite was true, except for large racing/simulation machines. Standard video game cabinets were manufactured in-house and fitted with arcade boards imported from Japan. Here's one of the most popular designs, called Video Robot:
Video Robot machine:
(http://image.quebarato.org/photos/big/2/A/6692A_3.jpg)
A coupe of them at an 80s arcade:
(http://www.retrogames.cl/imagenes/memo/vizz2.jpg)
Notice the car-audio speakers used in them :P I'd love to score me one of those cabinets and put a PC inside it.