Hi lostshopper,
Two of the links in my last post (one for the Baltimore area and one for the Philadelphia/Wilmington/Trenton area) includes the better options in your area that I’m aware of.
There are also some body type and sleeping position guidelines in the links I posted earlier (in the overviews) but I would only use these as very general guidelines because trying to “design” a mattress based on the specs of the layers is never as accurate as personal testing and can be more complex and frustrating than most people would suspect. It’s much simpler and more effective to work directly with people who can help you make good decisions both in terms of quality materials and in terms of helping to “fit” you to a mattress that provides the best possible PPP (Pressure relief, Posture and alignment, and Personal Preferences).
Given your lower weight though and the fact that you are a side sleeper … it would make sense to go with softer foams (either latex if you prefer fast response or higher quality memory foam of 4 lbs or more if you prefer slow response materials). There are many types of memory foam and some sleep cooler than others. You can read more about memory foam and temperature regulation in post #6 here) but in general … latex is the coolest sleeping of the foam materials.
The upper layers of the mattress, the quilting and ticking (cover) of a mattress, how deep you sink in to the mattress, the mattress protector you use, and your sheets and bedding can all have a significant effect on how cool a mattress sleeps and they are all pieces of the puzzle that can either enhance or reduce the temperature regulation of layers below them. In general terms … natural fibers in the ticking, quilting, and the bedding will be cooler than synthetic materials.
Hope this helps.
Phoenix