Not too many folks have the same tool needs as we do in the world of working terriers: packable, light-weight, but indestructable, tools for serious dirt moving.
It turns out there is one group who does, however: the folks who make dirt bike trails far from the maddening crowds
Trail Boss makes a shovel, saw, hoe, and a mattock/pick combination build around a three- or four-piece handle with removable heads. It also has a collapsible rock bar. All parts of this kit are very expensive, but considering who is using them (serious trail builders) I suspect they work as advertised.