I have no affeliation with this company. Found this little hole in the wall family shop that makes their own sandbags, flags, silks. Wasnt sure of the quality but was pleasently surprised. Plus for the heavier bags their almost half the price. I just picked some bags and they have some great prices. I like supporting the little guys when i can. Plus they sell to the bigger shops. Don't forget to check the clearance section 
Tell 'em Tim sent ya
http://www.canvasgrip.com/contact_us.html
Tell 'em Tim sent ya
http://www.canvasgrip.com/contact_us.html