Hmm Pretty art and unique style. Pricing art was always difficult for me as well. When I had time I use to price mine like this:

1-5K Portrait (depending on detail)
5-15K Half body
15-25 full body

I think you'll find that if you open an art auction during our upcoming Festival of Winter Night it'll go very well for you. We have a lot of art lovers here. Put your auto buy high like 20-50K I'm sure you might even get a few older CI's or EI's offered to you.