hi smiley
stargate on the back eh,try dialing it and go to the pegasus galaxy for the hols it will save towing :O).
sorry smiley sci-fi joke just could not resist it.
anyway is it a folding camper or trailer tent??, from the vague description "sorry" it sounds like it is either one of the early helios models of part van/tent or one of those all in one easy erection trailer tents where the roof section of the trailer hinges over the back to form the waterproof floor of the annex section, the canvas bit then forms an arch shape between the two doubling the trailer size. I am sorry I have no idea who made them but saw one once on site,
if you come back with some more info I will look through the data base and report back.
colin