Do you know where I could print T-shirts for cheap?

I believe there are machines you can buy to do it yourself. You might check a craft store.

I don’t know about places in Canada, but online try CustomInk.
Caveat: I’ve not tried this myself, but heard about this site recently.

How about Zazzle create your own.

If you have an inkjet printer you can buy transfer sheets that you print the design on and iron it onto the shirt. It only whorks when the shirt is lighter than the design though. That is probably the cheapest way to do it.

Thank you everyone I will look into it!

How complicated is the design?

I’ve had a lot of success with making stencils drawing or tracing them onto freezer paper. Cut out the shape and iron(glossy side down) to the shirt. You can now spray the shirt with bleach or use fabric paint on it. If you go the bleach route go light with it, too much will eat through the clothing.