Probably the one you'll most likely find available (rental houses, etc.) would be one of the Vision Research Phantom cameras. I think they are pretty much the go-to high-speed cameras these days (in fact the Panavision high-speed camera is a Phantom with a Panavision nameplate replacing the Vision Research one).
There are lots of Phantoms out there, most big camera houses will either have one or be able to direct you to one... there are some private Phantom owner/operators floating around as well.
I haven't had any need in a while, but the last time I was looking into Phantom rental I found that many of the rental places also required you to hire their Phantom camera tech along with the rental. I'm not sure if that is true of all of them.
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