Greetings to all those who have been watching this thread, I have good news!
First, I submitted a complaint through the Wisconsin BBB to the company listed on my product literature -- and that company was not Polar Ware. In any case the company was based in Wisconsin. Hence the reason I had to use the Wisconsin BBB. Anyway, I received a response from a company called Vollrath Co., LLC. Apparently, Vollrath Co., LLC now owns the Polar Ware name. So basically, long story short, the representative stated they would have their distributor -- LD Carlson -- find a glass sight gauge for me and would also give me a $50 credit toward the purchase of the glass gauge!!! Not bad!!
I accepted the offer. However, the Wisconsin BBB -- brain dead as they are -- dropped the ball and Vollrath never received my acceptance letter. So, I contacted Vollrath directly, exchanged a few e-mails with the account manager and he has agreed to replace my 15 gallon (60 quart) kettle less the sight gauge and sight gauge mounting holes. The exact same kettle I have, but without the plastic sight gauge.
Ecstatic over this solution, I agreed and my brand new kettle is on the way to my house.
So the Wisconsin BBB enabled me to make contact with the manufacturer, Vollrath Co., LLC -- they helped me to get their attention. But I believe direct contact would have also worked and a resolve could have occurred sooner. In any case, I'm okay with the end result.
glad it worked out!