Quite right Chris, it's just a piece of Hex bar with a 32 X 1.5mm pitch thread and a sharp taper machined on it.
Nothing fancy at all.
I'm sure the genuine Triumph one is made from a decent bit of steel as it would likely be going to dealers who would (potentially) use it time and again.
But for the private owner who would "hope fully" only use it once, mild steel would be fine.