Sorry to hear there are a few bits causing issue 😕
I never knew the Saab had HK speakers...... as I have the old rear door in my garage I thought I would see if it has a suitable replacement for you, it's still HK but unfortunately possibly the least inspiring looking speaker imaginable!
(you are of course still welcome to it free of charge if it will provide a temporary solution)
Edit: I think the rear speaker mounting looks to be smaller than the front ones so won't fit. Probably not much of a loss.