If you can't find any I would suggest getting a hi yellow albino and then buying the brightest yellow normal Carlsbad locality cal king you can get from Kerby. He breeds pure Carlsbad locality kings. I don't breed them but I live in California and have seen/caught many and can tell you that some of the brightest yellow genetics there are come from the Carlsbad locality. Plus some Carlsbads have so much yellow on them right from the wild they almost would qualify as hi-yellow/bannanas already. If you bred a real nice Carlsbad into the albino bannanas it would almost certainly improve the color and probably not take more then two generations to get them back to true bannana/hi yellows patternwise.
IMHO this would be a very worthwhile project anyway since many of the hi-yellow/bannanas out there(both normal and amel) have been mixed with black and whites and this has diluted the color intensity of the yellow.