Just to wrap this up, I contacted Recmar and found them very helpful over the phone
. I placed the order and it came in two days. I bought the shower track, hangers, rollers, and end stops. All of this looks to be of very good quality and I am anxious to install it. Again, thanks to RunningFish for finding this site for me!
As an aside, Recmar is an interesting company. From their website, they sell two lines of products - curtain rods and navigational tools (dividers, protractors, parallel rules, etc.). The owner must be a sailor!
In summary I had a good experience with them and recommend them for anyone needing shower tracks.