i just used one of the genetics calculator to calculate what a HRA x Banana would produce and look like. it just came back with HRA Banana, no morph name. so it might not exist yet, so not sure if it would be purple.

but if u want purple snakes from base morphs u can get a simple Mojave and mix in Phantom for Purple Passions. also mix Mystic into the Mojave and u get Mystic Potions. all have varying degrees of purple and patterns.

also i u are looking at double recessives - how about making an VPI Lavendar Snow? (VPI Axanthic Lavendar Albino) i bet those would look great!