Do you know this one?
No the large marcie does not come with the strap. The bag is quite large and it looks best worn over the shoulder, I think even if it did come with the strap it wouldnt look any good because of the size of the bag. If you want a strap you need to look at the small/medium marcie.
Could be wrong, but seems like I remember a large with a strap on NAP a couple seasons ago.
Yes, here it is: http://www.net-a-porter.com/product/98707