You did fine money wise - I saw that on Letgo listed for $300. Shay Arcade has the backglass and Pinball Resource has new pop-bumper caps. I personally don't like mixing old with new bumper caps but jmo. If you do go with all new I am looking to upgrade a couple caps on my Slick Chick - let me know if you sell any.

Bostonpinball.biz has it averaged out at about $1000 (ebay sales). The 2017 Mr. Pinball Price Guide lists it for $1450 in very good condition working.

You do have to be careful though when buying games as to not put too much money into it. This one you should be fine.

You should be able to remove any rust (Evaporust, Lightning Rust Remover, etc.) and buff out your legs, coin door,and coin entrance plate which would save you some $$$$.