New horizontal DOT tanks are still available with the new OPD valves, so the components are made. Guess it's just a matter of finding a licensed LP outlet willing to undertake the job.
Why don't you call Manchester Tank Co. at 1-800-877-8265 and ask in either the sales dep't or tech support section. Tell them what need and they may have an outfit that will do it.
Solar Tech Energy Systems, Inc.
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