I'd say, it's a selfmade camper-conversion. Basicially it's a Transporter, not a Bus, Vanagon or Multivan, because of the missing side-windows.
I don't know any VW Campers, which are based on a Transporter, except the canopy-camper-kits, which were made for the Pick Up and the "DoKa", the double-cabin-Pick Up.

If it's a syncro, I cannot exactly say. The chassis looks higher, but perhaps that from a syncro is a bit higher, not exactly to identify.

It looks like the European version, am I right? Anyways, was the Transporter-version ever officially exported to the USA?