Triangular vs. square hole-layout junction boxes

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I've got a bunch of existing Amcrest cameras that use the standard three-hole mounting layout that all the Amcrest junction boxes have, but recently got some newer AI turret cams (IP8M-2669, -2879) that use a four-hole layout that's incompatible with the existing junction boxes (grr). It looks like Amcrest doesn't sell any junction box that'll work with these so I'll have to use Dahua ones, is the PFA13C the right one to use?

I've also got an AMCPFB203W that it looks like I'll need to replace with an AMCPFB204W but was thinking of using another PFA13C to go from triangular to square hole-layout, it'll look a bit ugly but replacing the 203 with the 204 will be a huge pain due to its location. If I did decided to replace it, would the 204 be the right one for those cameras? Alternatively, is anyone aware of an adapter plate to go from the triangular to the square screw layout? Worst-case I might be able to hack one together myself from alu plate, but that's probably going to be a lot of work since I'll need something thick enough to tap for the screws.

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From some more googling it looks like a PFA130 will do as well as the hard-to-find 13C, but if anyone can confirm the above stuff that'd be useful before I go out and buy the wrong thing.