Googling "Pro HGH Symbiotropic" turned up several sources. Price is about $70.00 (HSI said the price was more than typical) for 40 doses.
I was trying to chase down the same question (What is this stuff and who makes it?) arising from the same HSI mailer (The 7 Most Dangerous Lies Your Doctor's Telling You) and stumbled on your message.
After twenty minutes of getting nowhere, I bit the bullet and paid to join HSI.
I looked up "Oregon" and "HGH" in their database and found the article from which the blurb in the mailer was abstracted. Oregon was where the formula was tested. HSI didn't name a manufacturer and I couldn't find a link to the source they use.