They are probably hard to come by and expensive these days, but if someone could come up with a kit or something to make these out of styrene/plastic and run them off of a 50cc 2 or 4 stroke I would be all over it.
Oh yes! - I was delighted by that Top Gear video I would love to own a P50; - it would be sooooooo nice to use to get about in the wet Winters we have around here. I love riding my electric Hercules tricycle, but getting soaked in a downpour is not my idea of fun
I've got a trike up on my workbench at the moment (Yes I do have a BIG workbench, - it saves my back and knees) and I'm toying with the notion of putting a lightweight van type body on it. A Raleigh replica would be easy to do and what's more it would be completely practical.
The Raleigh van was based around their utility type 'V' twin motorcycle intended for sidecar haulage, - so yes it does have a motor.
I like the Peel P50, but not the Trident. The Trident would bake you to death on a sunny day under that bubble dome. I was interested to hear it said at the end of the Top Gear programme that they thought the P50 was the best car they'd ever road tested.
That Berline would be a honey of a project. I guess a one off bodyshell could be made from fibreglass over a foam core. Some of the velocar streamliner websites have very good 'how tos' on building a bodyshell.