I liked the original Brubaker Box. I like the design and shape of it. If they do actually make a new one (the article above is dated 2014), I wonder how much it will look like the new one.
I think one could make one using the Faraday Future platform of batteries and wheels. One would not have to worry about getting parts from an older air cooled Volkswagen Beetle or micro bus. It would also make it green. I believe the Faraday Future platform (video) is adjustable.
I think an alternative to the above could be the engine and transmission and (lengthened) platform of the Smart Fortwo? The Fortwo has a rear wheel drive and rear engine similar to the VW Beetle. One could adapt the Box design to accommodate the radiator but I think it could give a little more modern look.