Not sure what Casters those are. I think Ernie Ball sells a caster set that might work if the diameters are the same. Also could try contacting Mesa directly if you don't find an answer here. But, if you want, you can order new Track-lock Casters from Mesa and the could probably be fitted on there. They mount flush and the Casters slide on and off in a sideways motion. To me, they are a lot better than ones that just pop in and out. They typically become worn over time and just fall out if you lift the cab off the ground.
-AJH