1 gun only primarily for range use, then 1911 9mm.
9mm - cheapest centerfire ammo.
1911 - great platform.
For range use, I usually opt for adjustable sights to allow for POA=POI.
The only 9mm 1911 I can think of in the $500 range would be an RIA --- I would look at RIA tactical 9mm.
Another one to consider maybe an EAA Witness Match 9mm.
There are also many good used guns: Sig P6, Pxxx, 3rd Gen S&W, etc.