I have mine scheduled under a separate rider with my homeowners insurance.
The weird thing is that a lot of people on the site recommend collectinsure, but when I tried to get coverage a couple of years ago the underwriter declined coverage for pinball and arcade machines under the reasoning that they "run on electricity". I even sent them tons of pinside threads where people talk about using collectinsure for coverage but they still reiterated that they can't cover pins. Very strange.