Sounds like Revell's customer service desk is being manned by people who haven't been with the company long. In the good ol' days anybody who worked for Revell would have been able to figure out what the Cutty Sark kit was.
I imagine what they mean by "serie number" is what's usually referred to as the kit number, or box number. The only reliable source I know of for such things is Dr. Thomas Graham's fine book, "Remembering Revell Model Kits." Its appendix contains the numbers for all Revell kits produced prior to 1980. I think the Cutty Sark kit got re-released at least once after that date - perhaps with a different number. But I don't think the parts inside the boxes changed.
There are a couple of partial exceptions. The original kit, released in 1959, had no sails, and didn't include studding sail yards. The first version with sails, H-395 (1966), had studding sail yards. That same year Revell issued a Cutty Sark without sails in another box (H-394). I'm not sure whether it had the studding sail yards or not. I believe all subsequent releases had the sails and studding sail yards. Also, the very first issue contained a couple of gears that linked the steering wheel to the rudder. Apparently that mechanism didn't work well; by the time my parents bought me my first Cutty Sark, sometime in the very early sixties, the gears had been deleted.
Here are the numbers from Dr. Graham's book: H-364 (1959), H-394 (1966), H-395 (1966), H-399 (1974), H-393 (1978). (The last one listed was the "Museum Classics" version, which featured a wood base, brass-plated mounting pedestals, and sails sprayed with a strange flocking substance that supposedly made them look more like cloth. It didn't.)
Unless the Revell people insist on a post-1980 number, the information you need should be in there somewhere. Good luck.
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