A Ruger 10-22 and several magazines. CCI's Stinger ammunition will do fine for serious work and you can practice and have fun with cheaper ammo. All .22 Long Rifle ammo will function through it flawlessly.
Where are you going to find CCI Stinger ammo at this point? I’m still betting that the ammo bubble its going to burst at least one more time before any serious ammunition laws are passed.
10.22 also comes in a .22 Magnum configuration. Good gun