Get the rubber mat for a truck bed and cut it to fit. I did that for my Pontiac Vibe in 2007 and moved it to my current 2009 Vibe when I bought that. I mainly did it for my dogs as it gave them a mat they could grip their claws into and not slip around.
Overall I have had the mat in the back of a Vibe for 13 years now. I can't recall the smell being overwhelming.