This site is a good reference if you haven't seen it already. -
http://lavender.fortunecity.com/lavender/569/negtoposdeveloper.html
I mix up my own baths as needed and it's very simple to do if you start with D-19 as your base developer. I only had to acquire the sodium thiocyanate, potassium dichromate, sulfuric acid and sodium sulfite.
I _am_ aware that it may be harder to get some of those item in Europe, so I sympathize with you. Using film isn't as easy as it used to be. :(