What kind or brand? I don't have much experience with multiple brands. I'm sure there are quality differences, but I can't give you advice there. We've only had one, bought it used and spent a lot of time cleaning it.
1/4" screen
For a brick...I'm not sure. You would have to experiment. My gut feel is that it should be the same size, but I don't know for sure.
Seriously, before you start running off in this direction, talk to a few of the brewers that are potential clients and ask them if this is a form they would accept. If the answer is no, don't bother. If the answer is yes or maybe, then move forward with the experiment. From the standpoint of oxidation, storage volume, etc. I don't see any problem with a brick. From the standpoint of usability, that's where it may get tricky.