I'm a 'tourer' so no expert on statics, but yours is a subject that crops up often enough, and the general response is 'no' or 'as rare as hens teeth'!
Sites like to profit from the sale of a van to you from their own stock/agency, and likewise buying your unwanted van from you at a huge discount, so they by and large won't allow 'bring ons' or 'off site sales', all in the T and Cs!
I have responded to similar posts many times, and the answer is you would be more likely to find a flying warthog. Very few site will allow this anywhere in Britain, let alone in any specific area, it's simply not in their interest. I usually conclude by asking the poster to let us know if they do find one as it could help others in a similar position, but as yet I haven't had anyone come back with a response.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets