The VERSA rig is now available. It was a collaborative design with Max Velocity and UW Gear.
It comes with both the 5.56 and 7.62 inserts. It is available for order here.
Reid Henrichs, owner/lead instructor at Valor Ridge put out a great video on a budget option piece of gear. He recommends using the Type 63 Chicom chest rig.
Check them both out.