Perrin and others sitting in the $120/pair range were right out- this is a loved familymobile, not a high-performance beastie.
For those looking for them, they can be a PITA to find via google searches and often they're listed as compatible for the Impreza only (even though Whiteline's own Literature states they're drop-in replacements for the Legacy). And at about $60 / PAIR, they're a steal.
Front:

 Whiteline KLC20A
http://www.kastleskorner.com/store/prod ... cts_id=786
Rear:

 Whiteline KLC19
http://www.kastleskorner.com/store/prod ... ts_id=1054
Sources:
Kastles Korner (http://www.kastlescorner.com) $59.99 / Pair
PDM Racing (http://www.pdm-racing.com/products/subaru_corner.html) $62.50 / Pair
Removal of old:
Yep, doing it on the ground on a level surface is strongly suggested. I was able to remove all the bolts with a 3/8 drive socket wrench and box wrenches.
Installation of new:
Slid into existing framework with only mild taps of a hammer for alignment of holes. Had to flex the swaybar a bit to install. All in all it was a 30-minute job on my buddy's lift with hand tools. Access would be tight, but doable, with car on ground and front wheels turned in approprate direction.
After the conversion:
Wow. Like night and day. Silent over potholes, steering seems to be aligned slightly better (is this just in my head?), body roll is greatly reduced, steering response is a bit better.