If you do not find the connectors in France, they are avaliable here a few places. This style of connector is not used very much here anymore. It is something linke 0.156 inch center to center, as I recall. This was a standard connector in the 1960's and 70's but was replaced by newer connectors that were based on 0.1 inch spacing by the early 1980's.
I would recommend finding something that is avaliable in your area with the greatest frequency and building your projects using what you have. I would then get just a few of these 44 pin connectors and make an adapter to adapt the 44 pin to your new choice. It does not really matter what you pick as long as there is more than 44 conductors.
I am not that familiar with what is happening in Europe, but surely there are surplus connectors, and mating project boards somewhere. I have used this technique of connecor conversion on a lot of projects. You get to make up your own standard using what you can find.
I did a search on google and found the following link that has the 44 pin SYM, AIM connector pretty cheap. If you don't find some, I could always order you a few and mail them to you. The postage would be much more than the parts cost though.
Dallas Shell
http://www.allelectronics.com/cgi-bin/c ... type=store