For electric power steering pump conversions it seems there are some pumps widely used;
Opel / Vauxhall Astra pump (TRW JER300) as used in Porsche cup
Toyota MR2
Volvo
Mazda
It seems the toyota one is popular and therefore expensive. The Volvo one seems nice in the sense that the CAN messages are available to change the operation of the pump (make it speed sensitive etc).
But are there any physical dimensions of these pumps out there? I would like to see which one would best fit. It would be ideal if I could keep the frunk clear, so mount it somewhere else up front.