New speakers for my Ka

Hello everyone, I have a Ford Ka built in 1999. The speakers in there are all the same really miserable and the right one is now just buzzing and roaring. I was already at ATU, but they don’t have speakers in their range that would fit in there. The size is 165 mm and the problem is that the speakers are very narrow (so the installation depth is that I think…) and therefore no boxes fit. Has someone ever built into a Ford Ka that was built before 2000 new loudspeakers. From 2000 they probably rebuilt the speakers because they themselves noticed that the old construction was total crap… Nu i really can’t hold out this noise anymore… I would be very happy to get information soon.