6x9 subwoofer recommendations wanted

[C2kev]

This is for my Saab. currently it has the seven speaker system (3 in dash, 2 subs/low range in front doors and 2 in parcel shelf) all running from the standard fit amp in the boot. the amp sends all the bass to the front doors only, the dash and parcel shelf speakers are mid/high range only. My plan is to disconnect the door subs and fit some 6x9 subs or just bass heavy 6x9s running lows only in the factory pre-cut 6x9 holes in the parcel shelf.

I don't want a sub in the boot, I just want it a bit better quality bass in the rear. it may end up sounding shite but I want to give it a go anyway as it is fairly easy to do

Budget no more than £70, recommendations please

Also don't say 6x9s look crap, they will be fitted in the factory cut holes and will not be seen

 

[Goodj]

Why not keep the door woofers anyway? can't hurt.
I thought the rear shelf speakers were supposed to be woofers too...but it depended on which audio kit it came with out of the factory.

 

[C2kev]

No, the rear shelf speakers are just 4" mids/highs with empty 6x9 holes next to them for the optional 11 speaker upgraded system.

 

[Goodj]

Ah right.
How about just rigging new 6x9 in the existing gaps, running an amp from speaker-level input?

That is if you can get a speaker level that hasn't had low-end filtered