The Mexican variant uses the same 4.0L as the ST, so with the right catylitic converter in place, I'm sure the vehicle could pass emissions.
Importing vehicles from foreign contries isn't for the light hearted and is best done through a company that does this normally.
<a href="http://www.foreignborn.com/visas_imm/entering_us/7importingyourcar.htm" target="top">Here's a link</a> to importing a vehicle into the US, just to know what you might be in for; be sure to check national and local regs for Manitoba though.