Amar' forever! :-) I live right next to Lergravsparken. There is a shop right past "langebro" Rømerdal værktøj,
http://www.romerdal.dk/ Nice guy that can get you almost anything. Throw him a mail, i think i paid 130kr/m for 12x4 trapez and around 40-60 for a nut, but you can make your own out of piece of the leadscrew if you are cheap:-)