Joined: Nov 2006
Posts: 19,810
Likes: 597
From: NJ, NYC, LI
Bikes: 1940s Fothergill, 1959 Allegro Special, 1963? Claud Butler Olympic Sprint, Lambert 'Clubman', 1974 Fuji "the Ace", 1976 Holdsworth 650b conversion rando bike, 1983 Trek 720 tourer, 1984 Counterpoint Opus II, 1993 Basso Gap, 2010 Downtube 8h, and...
Tell us more about your bike, though! What's the handlebar? The Shimano hub (very nice hub, by the way) comes with a twist grip shifter that fits only on an upright style (22.2 mm) bar. If you have a drop bar you'll have to figure out another way to mount it, which will blow your budget big time.
Sturmey Archer is now selling a 5 speed hub that comes with a bar end shifter, which will fit a drop bar. Well, last time I checked, the bar end shifter wasn't available yet, but should be out by now.
Assuming you have normal-sized wheels --26", 700c, or 27"-- you don't want the Sturmey Archer 8 sp hub or the Shimano Nexus 4 speed; other than that, anything will do.
Cheapest option, of course, is to find an old Sturmey Archer AW or Shimano 3 speed hub (if the latter, avoid the 333 model).