There is another POTO on Ebay at the moment...

http://cgi.ebay.com.au/Phantom-of-the-Opera-Pinball-Machine_W0QQitemZ180407772510QQcmdZViewItemQQptZLH_DefaultDomain_15?hash=item2a0124255e&_trksid=p3286.c0.m14

I don't know what they are worth, but maybe worth looking for a parts machine and one with a good playfield for yours?

Sold for $1825, not a bad price for that one, a tad too much for me at this stage. They do come up every now and again for a little less.
I will look for another i think, cant hurt to have spare parts.