Kotobukiya has an SDCC X-23 X-Force version Bishoujo exclusive statue with a limited to 1000 pieces run.
She features a new face sculpt and minor alterations to her costume to mimic her X-Force attire with a blend of comic accuracy and Ultimate Marvel vs Capcom 3 X-Force alternate costume accuracy in an interesting anime-like design.
She was available on the show floor, and will be made available through pre-orders on their site. You can check out a photo review of her at Tomopop.
Pre-orders for her are available here.
Update: Err, well they were. It seems to be sold out now.