I know I will get flamed for this, but check out the Norinco / polytech m305. They are a m14 copy and non restricted. You can get one new for around 499 or find something cool on the EE. They can legally accept a 10 or 20 AIA magazine as the AIA is made for a bolt action.
Not a Black rifle, but the OP may be interested due to the price point and upgradability. The downside is scope mounts ARE expensive.
Sorry for the Main Battle Rifle refrence

Not a Black rifle, but the OP may be interested due to the price point and upgradability. The downside is scope mounts ARE expensive.
Sorry for the Main Battle Rifle refrence



















































