The Source Fours are the most applicable fixture for using a scroller on. However, one word of caution, be sure to choose one company to get your scrollers and gel strings from and insure that when you swap out gel strings, all of the new gel strings have the colors in the same sequence from on string to another, other wise you could be in for a mess when you go to program a cue when you want a certain color wash. The two scrollers that I would recommend are the Wybron CXI and the Apollo Smart Color. If your school is willing to put some more money on equipment, try getting some Sea Changer Color Engines for the ETC Source Fours. The Sea Changer is a dichroic color mixing system that uses a hexachromic mixing system with CMYxG. This allows for a color palette with much richer colors and more vibrant light tones.
You can find scrollers for any light practicly. I would look at Chroma Q:
I have used these and the seem to work the best.
Is that a complement or insult?