MacoDirect (Germay) also has a Tetenal Colortec© E-6 3-Bath Kit for 1 litres and for 5 litres (besides several C-41 kits).

I also found a French store called Labo Argentique. They seem to sell a lot of chemicals, but I have no experience with them. Anyone does? See:

Prices seem to differ from store to store, so it is good to check for each product.