look into this thread, maybe now there is a newer more powerfull model of PSU but IMO that´s the better option.
[URL unfurl="true"]https://smallformfactor.net/forum/threads/complete-s4max23-worlds-smallest-4090-build-brickless-5l-s4mini-4090fe-7950x3d-800w-water-cooled.18499/[/URL]
Also you have these two silverstone psus
sfx-l 1200 w 125*130*63
[URL unfurl="true"]https://www.silverstonetek.com/es/product/info/power-supplies/ex1200r-pl/[/URL]
tfx 600w 81*41*150
[URL unfurl="true"]https://www.silverstonetek.com/es/product/info/power-supplies/FX600Platinum/[/URL]
If I were you, depending on the layout, I would organise everything and then decide wether it would fit me better one big 1200w thing or two smaller 500-600 things
One thing to take in mind is that the txf psu is 150mm long and the hd plex is 200-ish if I remember correctly. Given that an ITX board is 170 mm and the GPU pcb is more or less the same lenght, with one psu, you have 20mm left to fill and with the other it would protude 30mm outside so you have some nice room there to fit anything you like.
Scan the web for supermicro/HP server power supplies, I think there are some really nice ones. Look also into Delta website, they have some very nice OEM power supplies that you can use as a 12v generators.
