Why not get a colorimeter (€100-ish) and calibrate it yourself?
One that supports wide colorgamut and HDR?
Does it include all the software?
I have a Spyder5EXPRESS that claims to do WCG. For software, there is DisplayCAL - takes some learning but supports BT2020, ST2084 and HLG.
Seems not to be the most accurate device: https://www.avsforum.com/forum/139-display-calibration/2950178-spyder-oled-white-point-calibration.html#post55747318
The X-Rite i1Display Pro seems to be the better choice and here atleast a bit more expensive.
Maybe, but it was the cheapest 
The lack of sensitivity at low levels is a pain if you value your time, but it seems to give me sensible results - nothing like the errors in that post.
Because, having done that myself once, I can assure you it’s one hell of a learning curve. You’ve got to factor in the cost of software too - HCFR is unlikely to be sufficient.
Yup.
I see what you did there.