I'd go with a mountain triple and replace the large chainring with a chainguard, so you could have say 22/32 up front. Then throw an 8spd cassette on, say 11-34. The 22/34 combo will give you the billy goat climbing year (it's even slightly easier than 24/36). And you'd be using common and easy-to-find parts.

I know what you mean about some steep road climbs. Up in Blue Ridge, Georgia, which isn't far from me, there are some paved roads so steep that it scares me to drive my car up them. I start thinking my front wheels might come off the ground and the car will just fall backwards down the hill.