Gear parts for Sharan - Replacement parts

Hello everyone,
I have a Sharan, manufactured in 1997, with a 90 horsepower TDI engine and a 5-speed gearbox. The synchronizers in the gearbox are defective. I have disassembled it.
Does anyone know if the synchronization units are only sold as complete sets, or if the rings are also available individually?
Price would be great too.
Is it cheaper to buy a transmission from Ford (since it's a Ford transmission) or do I have to buy it from VW?
Thank you very much in advance.
best regards, stephan

Problem solved. Parts are only available from Ford. Synchronizer rings cost approximately €18 each.