Host would be a better term, but it's overloaded in ways that are useful sometimes, confusing at other times.
So there is actually no correct term for this that means only this other than perhaps switch which implies dedicated hardware used in a phone or other data network - which eventually is where all such server box functions will likely be located, that aren't distributed via a Consumerium protocol.
In the long run, with a fully Distributed Consumerium, there may be no need for dedicated boxes, servers may run transiently on many computers and it may only really be telecom switches that constitute bottlenecks for the healthy buying infrastructure - that is, there would really be no extra vulnerability for Consumerium Services versus the rest of the healthy signal infrastructure and Consumerium maintenance would be taken over as part of the Internet Service itself, with no need for Central Services.
There might still be a need to arrange with a guild or consultant to solve special problems and identify bottlenecks that keep the Consumerium Buying Network from expanding, and, some of these might require some "boxes" to be added here and there. At that point we'd call this a reflector box.