I would recommend you order a new one. The mileage is low, and the prices are pretty close to the MSRP anyways. For a few extra bucks you will get a new car that you KNOW hasn't been abused. I'm quite sure that all of the above have been driven roughly. Also, I'm quite OCD on the new engine break-in for the first 2-3000km. But that's been a debatable topic.
All 370Z's in Canada will have the touring package. Were too fancy for cloth seats. You don't need to mention that
Get the navi, it's great. Works very well, I'm quite happy with it.
Don't make the same mistake I did: GET THE SPORTS PACKAGE!!! it's so worth it! The rims are beautiful in the sports, you get big brakes and you also get a limited slip differential. Unless you are planning to mod these 3 items.
I know you didn't mention this, but get the hard top
the convertibles look good only if the top is down. I think they look friggen hideous with the top up.
Get the latest year model, and get the heated side mirrors. The 09's don't have them, and it pisses me off on icy days.
For winter: get blizzaks. The best ones u can. They'll be around $2000 for a set, and will serve you at least 2 winters. My Z did a great job last winter. LOTS of fun, yet quite reliable when needed. People say get sandbags, I didn't and I was ok. That's up to you.
I think that's enough for now. Go test drive the auto and play around the paddleshifters! They're really crisp and fun to use. Mine is auto btw. Since you're in the area, give me a shout. We can set up a small meet for us York region people and you can check out the differences between everything if u want.
That's my 2cents.