To do the neck 'bucker / single coil from both 'buckers / bridge 'bucker switching you'll need a 4 pole 3 way switch (12 lugs in total).
I don't know what EB uses, but there are a couple of brands that will do the trick. Dimarzio does have one- it's part # EP1111. Dimarzio Hardware (pdf)
Yeah, one thing I forgot about that Dimarzio switch is that the lever is pretty small.
So to match what you've got on the Pet I'd do what Ernie did: call customer service and order one from EB.
You might be able to find one from the original manufacturer (whoever that is), but this way you're assured of getting a switch that looks identical. (Also note- there are several different varieties of 4P3T on/on/on switches and the wiring is in fact different for some of them.)