as nick mentions it wouldnt do any harm to purchase some but not nesesarlily fit them yet.
if the rear springs are indeed selflevelling versions and the self levelling is not working then you would expect the rear of the car to be too low as it is now. or even look not too bad unloaded but be way too low with any passengers in the back ?
if the rear level is good however then it suggests the rear springs are std versions. ( maybee aftermarket that just happen to have those letters printed on ? )
springs dont physically "wear out " as such but can become weak over time and the indication of this is a drop in level . a spring cannot technically become weak and stay at the same height.
same scenario with the fronts. if the ride height is correct then the springs are good. yes they could snap tommorow. but so could a new one too !
With regards the rear springs, the car seems to sit ok when empty, but it does sag a bit with a load in the boot. I haven't seen another one to compare it to though, so I'm not really sure what's normal/expected.
With the front springs, again it looks like it might be lower than when new, but without another one to compare it to I can't be sure. Does anyone know the measurement between tyre and wheel arch for a 2.6 Elite?