Hi David and welcome to the boards!
Lots of different opinions here but mine is really simple.....45acp
In your price range a Ruger P-97 <just like mine
> would be an excellent choice
Or a base model 1911-A1 made by Kimber, Springfield, Colt....
If you are going to carry everyday, I might even consider a 9mm Makarov, East German or Bulgarian. They can be had for a couple of hundred bucks, the ammo is cheap and they are dead reliable. Shot bunches of them w/o ever a failure to feed, fireor eject!
Plus the bullet looks like a slightly shrunken .45
But these are just my opinions