Don't know who makes them, but they clearly are a custom-made proposition as the market for primer making machines is about zero.
If what I read in Ammunition Making by Frost is still true, the machines work on large plates with precisely located holes (like steel pegboard) to punch out hundreds of primer cups at once. Primer composition is hand spread into matching plates and the resulting pellets are then pressed into the cups. Subsequent steps are foil application, lacquering and anvil placement. It's mostly the handwork of making the pellets that sets the production cycle.
