Well from what I can see you have a very nice trailer and yes you have two collectible's as in one of two types, one being the military version which you do not have and the civilian model that you have.
The civilian one you have is not the highest on the scale to find as the military one's can fetch some good money, but the civilian one you have is also a pretty good find. military trailers during the WWII had several company's that built the trailers to specs for the military jeeps so they pretty much looked all the same such as the M416 one of the worlds best little made trailer for a tag along.
There are a few charges but not much that I can see that the PO(s) have done. One is the angle bar with the lights, that is not original as that trailer only had one tail light when new. Also those mixture of ugly trailer lights were not original. the hitch, hitch tube, crank stand were also added sometime after. The sad part to me is that
Military Lunette style Ring Assembly with Stand are gone.
That assembly (see picture) is as far as I am concerned made that trailer much more usable in unfriendly areas when of road.
Of course the wheels are not original as the trailer had what were old combat rims or older Jeep wheels that were to interchange between the trailer and a Jeep. You need to take care and clean that tag off and get the it back to normal, and also see what data you have on it.
You can do a we search by typing
The Bantam T3-C Page were you can see and read all about the Bantam trailer, pretty cool site.
All in all you have a nice trailer and is worth keeping, but thats up to you but I bet someone on Mud would love to have it, like me.

Enjoy that trailer.