Just a bit of a leftfield suggestion.
Reclaimed sports court flooring.
A few years ago I did my living/ dining room with a reclaimed badminton court from a tennis club in London.
It is first grade Canadian hard maple with not a single knot in it. I paid a cheap price but I had to de-nail it and stuff and there was some wastage of dameged boards.
I laid it with tongue tite screws on to an OSB subfloor. Then I sanded it smooth to get rid of the court markings and oiled it.
This cost me the price of cheap engineered flooring but is 18mm solid timber. To buy this stuff new would be over £100 a m2.
Check ebay
Ollie