It seems that WaterGroup have valves made for them specifically for the Canadian market. Some of those valves utilize various Fleck components which they license from Fleck.
My 'Tru Performance' softener has a model 3650 valve which I was initially lead to believe was a discontinued Fleck model. After being unsuccessful in locating a rebuild kit through the usual sources, I contacted Pentair to obtain their advice as WaterrGroup offered no assistance.
Wayne Ploense replied to my inquiry and advised that Fleck 5600 seals and spacers were used in my 3650. As it turns out, the 5600 piston and cap were also utilized but I had to alter the piston by removing the stainless steel cam yolk. It was an easy alteration as the roll pin retaining the yolk was easily driven out. Unfortunately, the brine valve on my control is a discontinued model and is not the same as the 5600 so I could not rebuild it when I did the main valve.
You may wish to contact Wayne at Pentair. If your valve utilizes Fleck components, no doubt Wayne will know which parts will be appropriate. Obtaining assistance at this time of year maybe delayed as it appears that Pentair had shut down previously from Dec 20 - January 2.
PM sent containing Wayne's email address.