I run a 1400, the big brother of the 540, plus a Hardinge HLV lathe, Plus a Beaver VBRP mill. They all run off a single, shared, Danfoss VFD. Without access to one of those, I'd probably go for a rotary converter.
Unless it's quite recent, it's likely that the motors are 415V star only and can't be reconnected to use 240 delta. With an over-rated VFD, a 240-415 transformer and a bit of configuration you can almost certainly run it with a single VFD, after all, that's what I'm doing, but it depends on the VFD.