Hi jlucas,
I’m not sure which link you mean but the tutorial post includes this link to a list of the members here that sell mattresses online and there are a number of them that sell component latex mattresses with individual layers that can be rearranged or exchanged.
Unfortunately there is nobody else can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved for anyone to make a specific suggestion about which mattress would be the best “match” for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) based on specs (either yours or a mattress) or “theory at a distance” (see mattress firmness/comfort levels in post #2 here) but the first place to start your research is the mattress shopping tutorial here which has all the basic information, steps, and guidelines that can help you with how to make the best possible choice … and know how and why to avoid the worst ones.
Phoenix