The words Original, Vintage, and Traditional all mean "different" things!.....Otherwise there would only one word instead of three to mean the "same" thing??
Having belonged to Car Clubs for the past 46 years, I have encountered the same thing with the words Antique & Vintage....and Custom, Modified, and Restored. As well as Custom, Hot Rod, & Street Rod?????
All mean different things to different people.
But back to Teardrop Trailers....lets throw another word into the mix (just to really stir the pot)

"Replica".
Here is the way my brain works: (or my 2 cents worth)
1. Original......Teardrop Trailers produced a manufacturer or home builder that have been left in their original condition. No matter what year they were produced.
2. Restored.....Same as "Original" but refurbished where needed to appear as they would the day they were built. Quality of restoration not a determining factor.
3. Vintage.......Teardrop Trailer produced or built prior to as set year? Depending on the age of the person interpreting or setting that year, this will vary. What is Vintage to an 80 yr old differs from what is seen as Vintage to a 20 yr old.
4. Traditional....Teardrop Trailer that is Built, Restored, or Replicated, to meet a specific criteria that generally defines what most people perceive as a Teardrop. Remembering that no two "Original" TD's were exactly the same, but fell into a "Sales Category" to meet the publics demand.
5. Replica.........Teardrop Trailer built as an "Exact" copy of an originally produced or built trailer. Here is where you can arguably bring in yet another word that is commonly used in the Automotive Restoration world...."Clone"
There!

Have fun with that!
My simple rule has always been ......Sleep in, Eat out, can't stand up in it to put on your pants.???

And as I said before, "It is about the people. And if they set rules to exclude you because of your trailer, then don't go! And avoid the drama."
Good Roads
Brian & Sandi