The series is called "MaK ZbV 3000" (Maschinenkrieger), and was originally started in the 1980s under the name of "SF3D original".
There´s a variety of kits, unfortunately, most are in 1:24th and 1:35th scale, since they mostly represent armoured suits, ie one-man units, similar to Space Marines, my "Wolf" battlesuits, and the "Buffalo" by Darkson Designs (which is very much and admittedly inspired by SF3D).
Here´s a link to a very nice site devoted mainly to the wargame, which was published in Japan and USA in the late 1980s (counter-driven, but you could adapt it to minis).
http://www.fluency.paintedtarget.org/sf3d/Here´s a link to a German online store who stocks a number of MaK kits. I HAVE NO PERSONAL EXPERIENCE WITH THEM, USE AT YOUR OWN RISK!!!
http://www.coolkits.de/kits/mak-kits.html