Could have been Rally-X. Same basic cab shape but with the horizontal monitor. Not sure you'd have so much room on the sides if you turned a monitor in a Ms. Pac...
assuming theres space on both sides of the cab, its plenty comfortable. my mame cab aint any bigger than that and i play fighting games with my friends on it all the time. someone gets too close, elbow 'em in the ribs.
That is either a PACMAN or GALAXIAN cab. The lines on a Ms. Pac & Galaga are different and a Rally X is not as deep (wasn't needed with the monitor set horizontally).
I think the bezel and angle of the monitor are throwing off the way it looks. Seems to be a horizontal monitor with the image horizontal if you hit enlarge on the screen closeup. Unless the cab is the ultra rare Mortal Kombat/Wacky Wall Crawlers: Zero Gee prototype.