I've seen xenopous laevis sold in three local fish stores in my area. I've only seen albino and pigmented frogs varying from light brown to dark olive green. I probably see more albinos than anything else. Never seen the rare stuff, xenopus.com is proably your best bet. I've considered purchasing from them myself now that the weather is warming up a bit.

Hey Jen if you read this, since you know a lot about the different variations of color. I saw an adult albino the other day in a pet store and I noticed his eyes were very red. My albino has black pupils and eyes that are more golden hue. Is that a separate morph?