Hi Ana,
You can see the specifications of the Pamper (assuming that it’s the latest version) in post #2 here.
There is also more about buying a used mattress in post #2 here.
The only way to know whether any combination of layers or components in a mattress will be a good “match” for you in terms of PPP will be based on your own careful testing or personal experience. The Pamper is the firmest mattress of the PLB lineup and would be too firm for many people (especially if they sleep on their side) but if it’s too firm for you then it would certainly be possible to add some additional softness and pressure relief with a suitable topper.
Phoenix