If skoda favorit or felicia has been sold in UK you can use REAR{ not front} springs from it, { again not from picup or combi they're far too stiff, just from hatchback}
I've tried rear springs from favorit, but seller cheated on me and sold me new pair from combi, not hatchback. The result was terrible, like welding your susp solid

only tires worked as source of amortisation. But some guys are using softer springs from hatchback and praise them, I'll have to try.
Remember though that 4x2 panda has about 2-3cm shorter front shock absorber than 4x4 and skoda spring is another two rolls longer!
here are some picts from my "experiments"
blue one is favorit{combi, as far as I am concerned it is the same length as hatchback, but thicker rod}
red is stock panda 4x4:
favorit:
panda 4x4 plus 18mm nylon spacers{ tyres 155/80-13}:
panda stock with spacers:
Raising your susp. brings camber problems, here you have picture of stock 4x4 plus 18mm spacers, and the same setup after changing the camber to about 0 degrees.{ by shifting by 4mm the upper shock absorber mounting hole}
and after changing camber: