So far I found only chain retailers who sell the big S names along the lines described in the shopping tutorial.
I am interested in some reputable local/ regional manufacturers and retailers.
Anybody has some suggestions ? Thank you
Hi bernouton,
Welcome to the Mattress Forum! 
The better options or possibilities I’m aware of in and around the Missoula, Great Falls, Bozeman, and Billings areas (subject to making sure that any mattress you are considering meet the quality/value guidelines here) are listed in post #5 here.
Phoenix