https://www.amazon.com/KMC-Card-Box-1000/dp/B0007N7P8K
Like 150-180 lands in top left compartment. 450-500 card cube in the rest. All double sleeved. The latches are practically impossible to come undone accidentally.
This set is really nice and is tempting me towards UB proxies with regular frames or re-arted nickname frames. Especially when like half the future releases are going to be UB...
I'm going to generic 1/1, 1/1 flyer, 1/1 artifact, and 1/1 artifact flyer on my next proxy order. Have to be careful to avoid anything tribal or anything that cares about color. Or house rule tokens to not have colors/subtypes. Either way.