I know it can be difficult to find all the chemicals you would like to use. But stop bath is easy to substitute vinegar, I am not sure of the mixture to use. But, be patient an APUG family member will soon provide us with the answer. I usually have a gallon of vinegar at home for cleaning, and cooking but I still buy Kodak indicator stop bath, just a habit after all these years, and this week I picked up some free Photo. Chemicals from someone on Craigslist.
So, now I will have enough for stop bath for the next five years.