Hi Seagiant,
I do believe that in order to verify whether yours is a Star or Phelps, you have only to examine the aluminum base to see if it is stamped Star Machine Works or if it is not.
If the seller represented it as a Star, then you surely have a claim against them, and should at the least ask them to demonstrate how they came to the representation... I would approach it as if it was a possible mistake and you can work with them if you feel there are some adjustements needed to price, or just to satisfy that you were not intentionally mislead. A good seller will take interest after the sale.
To the matter of whether Phelps or Star is better, you can certainly find many sides here. We do have some informational brochures, and the Phelps was a copy of the Star, so operation should not be different in any way.
I once paid a good sum for a Star Lube-Sizer that appeared to be in fair condition. Once it was cleaned up and inspected, it was nearly a basket case from misuse and neglect. It will take hundreds of dollars to put it back to operational condition, or many hours with a welder, grinder, and machine tools. I'd consider a Phelps in good condition as much preferred, $100 is not a bad price.
Verifying your Star dies fit and work means the most important part -- the quality of the dies that do the resizing -- is perfectly fine. Magma Engineering is always most interested in selling you a new product, but they also carry parts you can purchase to keep your Star or Phelps running just fine. Just do not expect to rebuild it for less than a new Magma Star, but Hycar washers, springs, and other incidental parts that may need to be replaced are reasonable and will keep yours running for years if you care for it properly.
I also recommend Stillwell Tool and Die at
www.sizingdie.com if you need any dies. I found them to be wonderful to work with and they make great dies that work with Star, Phelps and other lube-sizer tools. They can also rework dies so it would be a great site to check out if you are not happy with a die, need one specially made, etc.
If you have means to take some pictures of your lube-sizer, post them or send to the admin and get them posted so we can see condition and perhaps lend more support to your idea it is a Phelps.