It all depends on condition. Is the playfield in good condition? Are there any plastics missing or broken? If the PF is trashed, all the plastics are missing or busted, and the cabinet is gouged and has graffiti all over it, then no it is not worth 200. If there is no wear on the playfield, all plastics are intact, and the cabinet is is decent shape, then heck yeah it is worth $200.
There are replacement LED displays available for Williams System 11, just google "replacement system 11" for details. I don't know about replacement boards like there is for system 7.
There is a guide to repairing system 11 machines on marvin3m.com. Again, just google "marvin3m system 11".