You'd be better off just getting a standard "PC" monitor, there's nothing about Macs that needs a special monitor, any regular one will do and are typically much cheaper, people seem to pay a large premium for an Apple logo on the second-hand market for some reason even though they're no better than other screens. That price is too high for what is a pretty old screen, you could get a brand new 17" LCD for what they're asking for that old Apple 15"!