So, nice to stumble across this - I can't speak of my qualifications in this area
A few things to know - WI-FI blocking while grey area at best is quite legal to kinda "control" if you are a business or school that has a reasonable need to do so. Seeing as it is grey area however, one must be careful as it is not a free for all - see article below.
https://consumerist.com/2015/08/18/company-fined-750k-for-blocking-wifi-hotspots-at-convention-centers/While WI-FI jamming/blocking can be grey in certain situations - cell phone signal blocking, being a licensed spectrum is very very illegal, and something that they take very seriously.
AFAIK you will not be able to buy any american made good equipment without the appropriate approvals/permits which is not going to happen.
A faraday would be difficult/impossible to actually implement in most cases.
Only way would be to obtain one from overseas - however as others have noted that would be illegal to own and operate.