Try Penny & Giles.
The only time I ever heard of Penny And Giles was when I owned a DPA system waay back. The preamp wasn’t bad but it was far from cheap at the time.
I now have the fans but I’ve hit a bit of a snag, there’s no vent holes in the base plates, bugger.
I’ll have to cool it using the fans on the vents. Changes to my original plan now have to be revised, I’ll have to have a think about it again.