Y'know,
reloader28 might be onto something there...
Since availability is a problem, is casting your bullets an option for you under Estonian law?
That would allow you to select any bullet design from an almost infinite variety of molds (short of a hollowpoint, obviously) and a good starting point for a fairly hard alloy would be 4% tin, 11% antimony, and 85% lead- ought to give at least 20 BHN.