As an aside, one of the few lawyers I can stand to listen to on YouTube. He does well in presenting legislation and legal cases, and generally doesn't put clickbait titles on his videos or put out false information.
Just a suggestion, personally I would make sure to order the barrel with a threaded muzzle and at least a thread protector on it - just for the possibility of throwing a suppressor on it.
De-monetization wouldn't be quite as useful as you'd hope. There's a lot of youtubers out there that are out filming on public land mag dumping into fruit etc. that are already de-monitized, they rely on sponsorships/patreon/etc. There's lots of filming out on public land from content creators...
https://www.senate.gov/senators/senators-contact.htm
Pick a senator (or both) contact them either by phone or email (usually there's a specific option that you need help with a federal agency).
For your rep in the House: https://www.house.gov/representatives/find-your-representative