Hi bakhz, and welcome back after 7 years! 
Due to the upheaval in the manufacturing and retail arena over the last few years, we unfortunately cannot provide geographic lists of mattress manufacturers and retailers. The most recent post concerning them by @Phoenix is from 2015. As they are still open, it just seems that other consumers have not posted about them since then.
Several of the Trusted Members of the site located in Texas: Texas Mattress Makers in Houston
And The Mattress Factory in Fort Worth…these have all been vetted for offering quality products with transparency in materials and components, great customer response and generous return and exchange policies, and most ship across the U.S.
If you do visit any local showrooms you find interesting, feel free to share your experience so other forum members in the area. Also, if you have any questions on specific mattresses let us know and we can possibly comment on their potential suitability.
~ Basilio