I got mine from National Pool Tile in the San Diego area.See if they have one of those in your area or an SCP Distributors LLC or other pool construction supply place. Mike
3M sand comes in 50lbs bags and about $25-30 depending on the location. Each distributer has a little different prices but nothing to extreme to want to drive out further to get it $1-2.00 cheaper.
Let me know L Aquatics if you need it. I am driving up this Friday night to Fresno after work so I can leave it in the trunk. 50lbs black s grade unopened.