Hi bum back,
The bad news is that in order to duplicate a mattress you would need to use the same layers in terms of thickness and ILD, the same ticking, and the same fire barrier and glue the layers together (which PLB does). Layer softness and layer thickness both are a big part of how a mattress feels and the ticking is also a key component. In some cases minor differences can make a noticeable difference. The only layer that you could probably “get away” with different layering and still have the same feel and performance is to replace the extra firm talalay latex stability layer on the bottom with extra firm polyfoam. I doubt that you would find a manufacturer though that has the same layering and other components.
The good news is that if your target is similar PPP (Pressure relief, Posture and alignment, and Personal preferences) instead of another mattress … then you can use your experience on the PLB Nutrition as a guideline to achieve something similar with a different layering combination that would meet your needs and preferences. In other words there are different pathways to similar PPP. This would take a combination of technical knowledge, experience, and intuition in order to know how your body type and sleeping position may interact with different mattresses with different layers.
Local manufacturers would likely be a good option if they can customize layering.
There are also several members of this site who specialize in layered choose your own layers mattresses with zip covers that you could also work with to achieve what you wanted but again the layers would be different because they have different layer combinations in terms of thickness and ILD. Again … the target would be PPP that worked for you and was the rough equivalent (perhaps a little better or worse but in the range) of the PLB. These members are listed in post #21 here.
PLB glues their layers together using a water based latex glue.
There are also some alternatives for adjustable mattresses besides the Prodigy but regardless of what you choose, one of the better outlets, selection, and prices on the internet for adjustable beds is here.
Phoenix