At about $1500 real tilt-shift lenses are not cheap. (Long time readers will appreciate the correct spelling :). Instructable user Cpt.Insano created a 3D printed adapter that converts practically and Nikon lens into a tilt shift lens. Sadly, getting the lens further from its flange distance means that the lens will only operate in Macro mode, but I would assume that getting a Nikon lens onto a Canon body may work as Nikon has longer focal flange distance than Canon.
Anyhow, this is a really simple build, and all you have to do is grab the parts from the instructable, print them away and click them together.
You would have to do a bit of sanding to get the parts to work together as they are printed with zero leeway, but this is probably the better way to handle delicate assembly with rough 3D printers.
The first step is to print the files (you can either get the STL or get the original and adapt them to your camera brand) .
Then once assembled, you get a tilt-shift adapter that should work with any lens. Cpt. Insano used the Nikon 50mm f/2 which sells at about $50-$60 on eBay so that is quite cheap for a tilt shift lens.
Here are the results, changing plane of focus is not trivial when doing macro but it does show that the concept works
[3D Printed Tilt-Shift Macro Extension Tube | thanks for the heads up, Jason]