Sadly there is no one place and many places sell it for similar prices. Many retailers may even offer free shipping if the order is above x amount. Also if you plan on using the pistol in a competition find what it likes to eat. Check out some of the sight sponsored retailers. I've been doing the same thing here and one place will have x caliber cheaper than one place and the next will have a different caliber cheaper than the first. So look into them and see what will work best for you.
Also keep in mind certain ranges do not allow for steel core ammo, this tends to be cheaper but if you cant use it it's not really a savings. As a general rule steelcase is steel core. I picked up some Winchester steelcase that is lead core locally. A few things to keep in mind.
