While we don't yet have a dedicated case for the 4ms Pod64x, one of the cases in our PULSE line may be a good fit!
The dimensions we have on hand for the 4ms Pod64x are: (12.98 x 6.28 x 2.24) inches. If that aligns with what you have, we would recommend looking at the PULSE CASE FOR BEHRINGER TD-3, CRAVE, OR RD-6: (13 x 6.25 x 2.25) inches.