Will you have to have the front end realigned after the install?

If you're installing direct-fit replacements (i.e. the only type you should be installing in the first place), then no. Shocks don't set the alignment of the wheels. Unless you're messing with the steering system (tie rods and stuff), or control arms and bushings, alignment won't be changed.

The only way it would matter is if both the old shocks and springs/t-bar had failed miserably, and it was aligned previously despite that. That's an extreme case though, since even terrible alignment shops would notice something like that.

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The compatible Bilstein HD shocks were actually designed specifically for the Ranger, and ultimately used on certain OEM models. They're expensive, but they're arguably the best stock replacement you can get. Of course, if you installed a lift kit or something, the ball game you're playing is on a different field. Pair the wrong shocks with the wrong lift kit, and your drive will feel like sliding down a flight or two of stairs.

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2003 Ford Ranger XLT
2.3L I4 Duratec DOHC, 5R44E 5-speed auto, RWD, 7.5" Open w/ 4.10 Ratio, Gibson split-rear catback
Sonic Blue Pearl with dark gray trim