Thanks John. The only number on my housing is A16, but I am sure it is the 170 series. Couldn't find lenses only, so ordered PRT and STB full assemblies as the old ones were getting brittle. As you suggested, GO2Marine had good prices and next day shipping.
I hope to see you both at the Appal. Gathering this year. We are coming a week or 2 early to do some exploring.
Thanks again.