I wonder if anyone has hacked the $15 PC version to work as a coin-op game. Saving a couple of thousand dollars is a pretty big incentive.
Also illegal. The home version is almost definitely not licensed for public performance.
New dedicated deluxe cabinet games sold in the USA seem to be ~$6000-15000, depending on just how "deluxe", according to the operators I talk to. Redemption stuff seems to sit in the $8000 range. They'll pay it because it actually earns, unlike the videos.
Full conversion kits (artwork, PCB/computer, software, sometimes some control hardware) seems to run ~$4000-6000 depending on the game. Upgrade kits to jump from one version of a game to a later version (same cabinet and computer hardware, just software and some new cabinet artwork) seem to run ~$1200-4000 again depending on the game.
All this is excluding shipping, of course. Sometimes a local disty will cut you a deal and ship it to you for free or cheap if they want to be rid of it.