I've done my fair share of airbrush research and the Iwata lines are bar-none the best! Other companies make good 'alternatives' that will work well if you learn to use them but for ease of use and versatility Iwata's can't be beat.
I ordered my Iwata Revolution from Coast Airbrush (
http://www.coastairbrush.com/) since at the time they were the only ones who had it. Lots of modelers at rec.models.scale order from Dixieart or BearArt, they seem to have no problem.
I think the Eclipse series should suit your needs. If you feel the need to draw any finer lines than what the Eclipses' 0.35mm needle will give you, try the HP-C, with a 0.3 mm needle and big gravity fed cup. Nearly twice the price, but... :bandit: