Covers have to be fairly generic in order to be inexpensive. You certainly can contact a local canvas shop and get a quote but, trust me, you won't like the answer.
I'm puzzled why you'd want to cover a "rigged" AI. It takes all of 10-15s to drop the mast and lay it on the yak. Once you do that, a square - good quality; i.e. 10+ mil - vinyl tarp will keep your boat protected for a few years. Just don't drive with the cover on

I have both a Getaway, a couple of AIs and a couple of iTrek 9. I get the Hobie cover for the Getaway because I don't want to drop the mast every time and it's easier to use the fitting cover. I use rectangular tarps for the AI (16 x 20 to go over the entire trailer with 2 AIs), and I'm still looking for suitable bag for the boards as none of the generic ones fit and Hobie hasn't come up with anything - Hobie are you listening?
So in your case, drop the mast and get a tarp - easy-peasy.