I have not used any of these vendors, so I can not rate them or make suggestions. I have researched the various offerings and these are the ones that consistently got good ratings and offered lower prices. As the saying goes, use them at your own risk. 😉 But please let me know if you have an exceptionally good or bad experience so I can take that into consideration. There are also the well known ones like Staples, CVS, etc. These are in no specific order, and they all offer frequent specials:

 

Canvas Print Factory

Canvas Discount

Poster Print Factory

Canvas Champ