They seem to be out of the passthroughs for a little while now. As far as the ECOpure, if you're not going to order any additional but just what comes with the kit, you can put a comment on the order when placing it, or phone/email and request an alteration - in my experience (and others posted on the forum here) the good folks at Innovapor are great about handling such alterations. So for example if you're ordering the double kit and wanted half and half of two ECOpure flavors, and two of the batteries blue two green, they're likely to accommodate that if you just ask.
My suggestion would be to phone ahead "General Inquiries: (801) 557-7773 If we don't answer, please leave a message and the best time to return your call, including time zone." you'll probably get Mark on the line who always seems happy to chat with customers and help out.
j