I love living in a place where a registry is illegal. Sic semper tyrannis Newsom. Why don't you do something about the illegals, or real crime?
308 is a great round, very flexible, as for what you want, you know better than us, first of all laws, than your budget, you seem like you want an M1, so look into them. Personally, while i have a maybe boner for DAKKA carbines, the SOCOM is kinda not great for most users. Look into a match (imho) for most. FAL/G3/CETME always based (assuming made right PTR does good work)
Also lot of options for single shot, or bolt. So the round has a lot of offerings too. While I am a collector and into mil surp, SCARs are pretty fucking nice weapon systems, esp if you want to do tactical shit I'd like a SCAR over an AR10/180.
If you're looking into high speed stuff, there's a few guys here who can help.
I didn't get much in my last review, but I'm still thinking I need to finish my AUG build but that's more time than cost at this point. I'm lazy and currently sipping Jefferson (ocean) and pressing some 7.62x25 vs trying to work on some retard euro space gun that's probably smarter than me.