JDM HU replacement

[DKL]

I have recently bought a jdm import that the only other UK owner swopped the original Japanese HU out for a UK one. The car has 3 cameras, rear, front and under the passenger wingmirror.
The new radio is a Sony XAV-AX1000 (6.2", 15.7 cm) so no satnav but it allows some connectivity but only 2 cameras work.
I'd like a full satnav, DAB system but other than bluetooth to connect to the phone I'm not really bothered by carplay or android play or whatever.
Satnav needs to have maps on board, memory card or similar and I'd like the maps to be searchable and/or movable - I'm used to Merc systems and like to be able to move the maps about. I rarely use the navigation part of it.
Ideally I'd like all 3 cameras to be accessible.
I don't think I'm up to fitting it unless possibly if it's a sony unit and the connections are all the same!
So any suggestions, so far some Pioneer units seem to have what I want but most only support 2 cameras.
Thanks

ETA A KENWOOD DNR4190DABS appears to fit the bill, a 7190 is 7" so not sure that will fit.
What sort of costs are involved getting these sort of things fitted and working?

Edited by DKL on Thursday 21st August 11:50

[MattsCar]

Size of the screen makes no difference.

They are all designed to fit in an industry standard double din sized space.