'96,
Suggest you get a sense of all your options. O2 is essential, but other strategies, like the D3 regimen and busting, can also make a big difference. Please see this file: https://clusterbusters.org/forums/topic/6213-basic-non-busting-information/
Note that Dave D says, "I'm one of the fortunate ones that have found success with O2 concentrators." Most people don't get real success with concentrators. In the file above, you can learn about (and further link to) welding O2 information. You shouldn't be denied by your insurance (unless it's Medicare, Medicaid, or another government program, which won't pay for O2 for CH), but welding is a good way to go.