Hi needhelp,
You can see my comments here about Latex Systems here and they make high quality 100% natural Dunlop latex yes.
Their website isn’t loading at the moment but the wayback page here will give you a sense of at least some of the densities that they manufacture.
The retailer you are buying from should be able to provide you with the information about the densities or ILD ranges of the cores or toppers they sell. Post #2 here has some comparisons between different densities and ILD ranges for Latex Green which also manufactures 100% natural Dunlop and would be similar to … but not the same … as the density / ILD comparisons for other manufacturers as well.
Phoenix