If you're a Costco member, and you don't feel like driving to the Costco store, you can get a bottle of Kirkland Signature 600 mg (+Vitamin D3) calcium tablets shipped for $6.99 plus tax. Offer ends October 7, 2012. There's also a sale price on multivitamin tablets.
If you are not a Costco member, you can pay just a little more for Spring Valley calcium tablets from Indy Outlet Center. With shipping the cost is about $7.50, depending on your zip code. Limited stock.