Boler started manufacturing in 1968, but only frenched the rear taillight on 13' trailers from 1972 to 1988.
Those door hinges are 'three-bolt' which is what
Scamp uses and also other egg trailers, like the
Eco. Boler uses a similar hinge, but it's only a 'two-bolt' on the body of the trailer.
Scamp used
windows like what's on this trailer at the front and back on models built in 1972-1973.
Did you look for the
VIN? It should be right here:v
Once you locate the
VIN, and IF it's a Scamp, see if anything here helps you decode it:
https://scampowners.com/scamp-trailer-vin-decoder
Good luck

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