In the states any unique attribute your 7 might have will help the sale by being a story and part of ethos/lore of the specific car that the an owner gets to enjoy and tell strangers, with that said it won't really help resale much as any authenticity of anything isn't valued on this side of the pond.
Also any car that wasn't directly imported as assembled isn't really authenticated as anything by Caterham themselves as they are sold as "kits" to here and owners/dealers assemble them as "replicas" even if they are built identical. A lot of specialty monikers that Caterham designates were factory assembled, ergo any car built here will never carry that title. Caterham doesn't look to give any special cars for people to assemble if they put their name behind it. I don't believe R500's were ever sold as kits for example.
I say that in particular because of "Superlight R"s like I have that are stateside. People could order "SLR" packages and get them built as "SLR"s but the engine is different (Zetec was used in the states and Rover was used in UK, which we couldn't get) and the cars weren't factory assembled so they never got an official numeration plaque. With that said some did get a non numerated plaque and all the stickers and other options are present to make a car an "SLR" (replica).
The cars are already peak uniqueness in the states (less than 50 sold a year and about 500-1000 total here) so anything else that could make the specific model unique gets lost in the weeds of it looking like a spaceship to begin with compared to anything else on the road.