Dyno time real data would be beneficial and probably the best selling point of an aftermarket device like a header, especially on a 4 cylinder motor that deserves more horsepower. If done correctly, it could also help the manufacturer of the header, tune and tweak the header perfectly. Torque, horsepower, rpm, gas mileage, etc, increasing for the best available price can not go wrong.
There is also sensor fittings and gas recirculation fittings to be concerned about for the smog minded buyer. On my restoration T-Bird headers, I installed a special Bosch wideband sensor kit with the an AEM gauge which will determine fuel mixtures precisely for adjustment.

People in the forum need to really get together on something like this and make a purchase as an organized group. Remember that the larger the order, the lower the price can be. Shipping cost would depend on your location. Start saving your money!

I am sure that when the header is close to producing, a thread, will or should be made just for forming a group buy effort.

One last thing I thought of is coatings. I don't know what or if the designer will be offering coatings for the header, for example; Ceramic, Chrome, Plain, but if so...what additional cost might be.

Thanks Claych for the usage of the vehicle, which the forum I'm sure will be grateful to whom purchases one of these headers. By the way, since your loaning your truck for the creation, can I borrow your truck for a while after the header is in place also? lol JK!

Here are a couple examples of Tri-Header designs for those wondering what a Tri-Y header might look like.
tri-y-headercollector.jpg