£100 is far too cheap if the game is complete. But you equally have to be realistic. Even if you bought the parts, unless someone fixes it for free, the labour to get this thing going again could prove uneconomic. A dead 1980s game like this might very well require things like
New mpu board £190
3x linear flipper rebuilds £75
Rubber kit £20
3x new flipper bats £20
Mix of things lke a couple of coils, couple of plungers, couple of switches, pop caps, plastics, lane guides, few new connectors, few fuses ... £100 before you know it
Thorough clean, strip the top of the pf down
And then there is the work. Have a look at this thread to give you a flavour. This game is the same sort of thing as yours, same cabinet, same electronics (just different roms) ....
http://www.pinballinfo.com/communit...pac-maze-another-obsessive-restoration.34712/
At the end of it 600 to 700 sale price perhaps
So after you have checked the fuses in it, if it is still dead, flogging it to an enthusiast stupid enough to put 10 to 40 hours of labour into it is probably the way to go.