ASG STI duty one mags

[Ditch]

I'm having a real hard time finding spare mags for my pistol, does anyone know of any compatible mags? Its hard to even find a picture, so sorry for the links:

http://cdn.airsoftsociety.com/forums/attachments/f8/4300d1304614544-magazines-sti-asg-duty-one-uk-image-3832541345.jpg

http://cdn.airsoftsociety.com/forums/attachments/f8/4301d1304614579-magazines-sti-asg-duty-one-uk-image-2361874943.jpg