Two things,
First Thing and this is important : for Brian F.,
Looks like a machinist's home-made special where the maker might have been inspired by an Ocean City Phantom and a Meisselbach Tripart.
What is an Ocean City Phantom?
Second Thing and this is pure speculation: for Brian P. --- That is a very interesting reel. I feel the origins are Ocean City. In the 1920's, Ocean City was selling a small freshwater reel named the E Z 2 Part:
This was a tubular frame reel, like the Meisselbach Tri Part; but, different. On the left is the Tri-Part and on the right is the E Z 2 Part:

As you can see, the Tri-Part has a threaded ring that secures the side plates to the frame by screwing onto the thread on the outside of the tube. Your reel has knurled side plates that screws into the tube like the Ocean City.
The Ocean City design also rivets the stand to the tube like yours is done:
I feel your reel may be a Ocean City prototype. It is very similar to Ocean City design.

The dimensions of you reel are bigger than an E Z 2 Part model. The E Z 2 Part is a small bait casting reel. I feel the design similarities are there. Another interesting point is the handle knob on your reel. It is a exact duplicate of the early Penn 109 handle knobs in terms of shape, which could date your prototype to around 1940.
I think your reel is a great find! There are also a couple of other tells. The free spool lever and star wheel look like they were stolen from Pflueger salt water styles. The bridge in your reel is a pivoting Kopf type bridge which Ocean City used on many of their early reels.
Obviously, your reel is a prototype or a home built. Because of they level of quality, I feel it is a prototype that should have never the factory. IMHO.....