I have an old (1997) Vision R-85 recumbent tandem that is my wife's and my pride and joy. We ride it about 2000 miles a year. Recently I replaced the chains, which had stretched considerably, and not surprisingly I realized the freewheel cogs are also worn and in need of replacement. The bike has beautiful and rugged Phil Wood hubs with a 7-speed threaded freewheel, currently a Sachs 12-28, which is no longer made. The only 12-tooth 7-speed replacement I can find is a 12-19 racing model, not something that would ever be used on a recumbent tandem. I can find 13-28 replacements, but I really don't want to give up the 12-tooth cog, which is extremely useful when powered by two riders with a tailwind or on descents.
Is there a source for a 12-28 7-speed threaded freewheel anywhere today?