Update #2. I decided to that a good night's sleep would help clear the gas fumes clouding my mind. Apparently, that was a good idea. I climbed back into the car, and had the pump and assembly out in less than 10 minutes.
Drove the Land Rover down to Advance Auto Parts with part number in hand, got the new pump, and brought it home to install. Reinstallation wasn't too hard, and luckily my mechanically-inclined girlfriend has a photographic memory and knew exactly what hoses went where, and got everything put back in place.
Now, the moment of truth...turn the key, crank once, crank twice, crank three times....poof! A small cloud of grey smoke and the engine roared to life. I put some air in the tires, tightened everything down, and took it around the corner to the gas station for a fresh full tank of 93 octane. The car drives just as well as the moment before it died. Having sat for awhile, the brakes have picked up a fair amount of rust, but that will burn off over time. The belts were a little noisy, but quieted down after I applied some belt dressing. The only noticeable difference is that I can hear the rear wheel bearings now. I guess sitting since August or September didn't do them much good. Well, just another reason to wrench on the old beast.
Anyway, thanks again for all the help. I feel very satisfied that I was able to diagnose and fix the problem, and once again have my beloved SVX back to life.
