In the Kansas City market place--the above stone can be purchased at the Home Depot--maybe a little more white than the traditional yellow

i go into the hood & look for buildings being demolished. the bricks are always recycled & sold but there is not a lot of interest in foundation stone. it's not as uniform as the stone in your photo but good cut stone can be found & the price is right.

The blocks in the picture are referred to as retaining wall stone and they normally come in 8" widths with different thicknesses. I searched for landscape supplies and found this Kirkwood Material Supply Inc - Kirkwood - Saint Louis, MO (314) 822-9644 they should be able to help you source the wall stone .