Notice some of the good manufacturers recommended here: Dozier uses D2, Chris Reeve and Bark River use A2 -- high carbon is the way to go for tough and sharp daily use knives.
There are good stainless steels, from 12C27 to S30V, but you could be paying more and not getting any real advantage.
Busse and Strider and Chris Reeve have very strong blades for a lot of money. Spyderco and Benchmade and and Bark River will get you through the day without breaking the bank.
What duty belt ... game warden? Bark River would be ideal, especially something like the Highland or Fox River. Don't be put off by the thickness. I have the Rogue, Highland, Wolf River, Micro-Canadian, and Micro Slither, and I keep them in the kitchen for food preparation. That's a convex edge. it cuts like a much thinner blade, and resists dulling.
If you aren't sure about Bark River, take a look at a Chris Reeve One-Piece that's a lot like the Sebenza: the Sable. From time to time, you can get a Sable III with the 4" blade. My favorite knife.

The Sable IV is 5.5" and a beautiful general-purpose outdoor knife, too.