You can deal directly through Ed on his
blog site
http://www.airsoftretreat.com/review...uct=224&cat=10 - review of the edgi kit
In my opinion, I'll lean a little toward a laylax spring and spring guide, but everything else EdGI.
Keep in mind that the inner barrels are designed to fit the outer barrel length; you can't extend it past the barrel cap and hide it with a silencer (without modding). He's in the Philippines so shipping can be expensive.
EDIT: I believe if you go to the Edgi usa site, you can find several US retailers that sell his products.