I made my own diffuser a while back but it wasn’t very optimal.
I discovered while looking for material for a new light that the translucent white-ish caps for stuff like Cashews or Coffee fit perfectly on my TK70. They also provide just enough diffusion without eating up much lumen output.
One more millimeter diameter and it would just fall off. 1mm more and its likely too tight to get on. So it was a pretty lucky find and nice coincidence.
A diffuser makes the TK70ish type lights WAY more useful as worklights. Otherwise even with low power, you get a very bright hotspot that tends to drown everything else out. Try it!