Check out the Sig P228 or the newer Sig P229 I prefer the P228 because it balances in my hand better. Think smaller P226.
If you are looking for a single stack look at the P225. I know where there are some really choice P6 which is a contract surplus gun for $400. Not as low as the good old days when you could get them for $300 but not to bad in todays market. These are mini P220s in 9mm.
My budget choice would be a Sig SP2022 .... If you do not mind a poly frame this is a great choice which can still be had for around $400 NIB.
CZ P01 as others have said fits the bill....
