This website guarantees it's items are authentic & states they are evaluated for authenticity before they are listed. It also states they have a lifetime guarantee of return if any item sold is proven to be unauthentic. They do not accept returns without written proof the bag is unauthentic from an outside authentication site.
The pictures look a little awkward but that may be from camera angle or if it's over stuffed. From the pictures provided, it
appears to be authentic but it would help to see more pictures of hardware & interior.
The measurements seem a little off to me but it may be where the measurements were taken on the bag. The measurement given are 28 x 27 x 11.5 CM which translates to 11.02 x 10.63 x 4.52 in inches. Different retail sites give slightly different measurements for this style bag. For example:
Amazon says 10 inches high 11 inches wide, MK site says 7.75 X 4.5 X .75" (which makes no sense to me) & Zappos say 11bw x 4.25 d x 10h. Different sites give slightly different measurements but the measurements still seem to fall into the correct range.
While this is a Malaysian site, it appears they have been selling designer items since 2010. I would say you would be safe purchasing from this site. CinthiaZ or Jojon21 may be more familiar with the validity of this site than I.