E30 convertible speakers
 

Hi i'm after some advice about rear speakers in the E30 convertible.
Unfortunatly a former owner has removed the rear speakers, so I need
to install some but from what I've read it's not that easy to find
aftermarket 5.25" speakers that are shallow enough to fit in the
standard speaker locations without touching the structural metal
behind. It looks like depth and also width of magnet are limited. I
don't need anything amazing, just something that fits without altering
the car and sounds ok without costing a fortune! Has anyone got a
recommendation for a current model speaker (in the uk) that fits? The
fronts are Pioneers coupled with original factory front tweeters and a
normal Sony headunit, no amps or anything..

thanks in advance. Mark