Hi ekim,
When you can’t test a mattress in person (or a very close approximation of an online choice you are considering) … then your best source of guidance will always be the online retailer or manufacturer themselves because they will know more about the materials and components they use and which of the options they offer would likely be the best “match” for different body types and sleeping positions based on the “averages” of their customers than anyone else and are in the best position to help talk you through the initial layering choices that would have the best chance of success (see mattress firmness/comfort levels in post #2 here).
I would also keep in mind that ILD specs are only one of several specs that can affect how soft or firm a layer feels (see post #4 here) and also that ILD ratings aren’t comparable between different types and blends of latex (see post #6 here). The Mountaintop Continuous pour ILD’s you listed for example won’t be a close match with other types of Dunlop latex.
An online component mattress can certainly make a great choice but outside of testing a very similar mattress in person (same type and blend of latex, same layer thicknesses, and a very similar cover) I would always base your choices on a more detailed phone conversation with the retailer/manufacturer that sells them.
Phoenix