mHBOT News: The USA’s last 7psi Portable Hyperbaric Chamber for less than $20,000. There is only one final 7/9 psi chamber available before Newtowne runs out for good. With Newtowne Hyperbarics permanently discontinuing the manufacture of their higher 7-9psi models, once this last chamber sells, the next choice for a high pressure hyperbaric chamber in the US will be available for around $50,000.