Marco,
The tetenal toners are still in production, and they make two, the first is a traditional two bath Sulphide toner,the one that smells of rotten eggs, and the other is the triponal, a variable two bath toner, you add the toner control part to the toner to control the color of the sepia tone.Having used the Classic sepia toner and the Foma toner I would say that the two are virtually the same and I would opt for the foma product, which is a traditional two bath odorless sepia toner, as was the Classic,
Richard