I hope this isn't too off-the-wall, but what about ASF? I'd suspect their dander and hair is significantly different from the domestic strain of Norway rat commonly sold as feeders - perhaps the difference is significant enough that you can handle being around them.
If it does come down to looking at other types of snakes, I'd like to cosign the recommendation that you consider the Antaresia pythons - they are hardy, active, curious little snakes with big personalities.