There are not many speakers that fit especially in the coupe.
The few that fit in the coupe doors without modification are Focals
and Jehnerts. Also true for the floor but the choices are in the link
at the bottom.
If you were in the US I would automatically tell you to go to these guys
as they can give you a one stop solution.
I just got my system form these musicar in myself
You will need the Technic Harness no matter what you do.
You will need a JL Cleansweep,ms-8 or an amp with processor to
flatten out the Head Unit output so you can decent sound