I tried telling you I have DONE what you are trying to do!! I might just make you one if you have some time (month or so) for me to get caught up on other stuff. I can make one for a stock subaru turbo again, but I just dont have time. Buying the one from that guy will be pointless for you. Its not going to work for what you want to do because its for a large T3/T4 turbo flange and the direction for fitment wont work even if you got his and replaced the T4 flange or V band flange he offers with a subaru flange it wont work.
You need to buy 2 of these and make one from scratch like I do.
What you are trying to do here is not hard to do. BUT nobody makes a bolt on kit for this that im aware of. you have to make it youre self. If you dont know how to or dont have the tools to do so. Well you shouldnt be messing with it until you can just buy something thats ready to bolt together.