Edging Brick Mold, Circular Pattern

Edging mold and insert for a 7 foot dia. cast concrete / stone circle. Designed to be placed over 75mm (1.75 in) tall edging (see pics). I plan on printing several of these molds from cheap PLA with a 0.8mm nozzle to cast several bricks at once. Planning to use quick-set concrete, sand, a tan colorant and a liberal amount of mold release / non-stick spray as well. Project pics coming soon.