I bought this one
http://www.conrad.de/ce/de/product/515213/Hutschienen-Stromversorgung-Serie-TBD2-ACAC-24-V-AC-24-W-Comatec-Inhalt-1-St?ref=searchDetail
This one is available in a range of watt ratings. Depending on the number of stations you want to use at same time you might have to choose one with more or less power.