In the same All-Terrain category as those SilentArmors vaporware, Pirelli very recently came out with a Scorpion ATR sized 255/55R19, the tread looks a tad less aggressive, but unlike the Wranglers they are available now.

If you are just looking for grippy tires to negotiate snowy and icy roads, and not necessarily to take your LR3 off road, dedicated winter tires such as the Pirelli Ice & Snow (same size) may actually do a better job than either ATs above, IMHO. TireRack lists both, check them out. Someone over on rr.net (with a RRS) has ordered the 19" Pirelli ATRs and will report back on how he likes them soon.