You might also look at the Spyderco Mule series. Spyderco has put out mules in a lot of different steels, from high-performance carbon and tool steels to ultra-high-performance powder steels, stainless and non-stainless. You can find them with or without handles on the secondary market, but you can add inexpensive bolt-on handles and get a simple sheath, or have a custom maker put high-quality handles of your choosing on them.
The blades are 3.5 inches long. The thickness at the start of the full flat grind is well less than one-eighth of an inch (0.115 inches), and the blade has a strong distal taper. At mid blade, the spine is just a tenth of an inch. Drop point and ground thin. These mules make high-quality, general purpose knives with thin, high performance grinds. And Spyderco does a good job with its heat treat.
So for your price, you can get the steel of your choice, the handle of your choice and the sheath of your choice, all with a high-quality, well heat treated blade with the geometry and size that you're seeking.