Whitch springs should I buy?

[pjusken]

After having a strange sound, coming from the right rear suspension of my car, for some time now I have more or less concluded that I need to change the springs. When I turn left, the right rear wheel sobbs to the "top of the wheel housing" (don't know the name)

I have already changed the dampers, but it still sobbs whenever I drive over bumps etc. If someone have another idea, about what it might be, then I'm more than greatfull for advice.

Otherwise I need new springs for bouth my rear wheels, and then.... Whitch springs will you recomend? (I don't want to lower my car, but I'd like som extra stiff springs, like heavy duty springs or something)