There are many places that sell these type of satchels bags for one, Yesstyle.com. It has quickly become my go-to for Asian clothes (if only I could afford to buy something every month!) and they have a nice selection of satchel bags like the one above-or handbags in general. Another mention is a wholesaler clothing site called Sammydress.com.
These are just a few examples of the various handbags, clutches, and canvas available on their site. The prices are pretty cheap like less then $20 for their stuff but it is a wholesaler place so the products might not be as the pictures show. I haven't personally shopped at Sammydress, so I can't tell you how good a quality their products are, but going off on the reviews its either hit or miss. The only thing I would say is to take extreme caution like with any other online store you buy from. I've been on a hunt for affordable accessories as well as clothes with the Asian style so if anyone knows of other places to buy from please let me know.