I regularly use applications I purchased (licensed) years ago, but that aren’t available today. That doesn’t make them exist “out there”.

That depends how you define 'out there'. I was using it in the sense of 'out there in the world' rather than 'her new haircut is a little out there'. So your having those applications would (to me at least) mean they exist 'out there'. So did you have any information on Bembo BQ?

My point is that there are several fonts that were commercially available at some point and, for a reason or another, were retired from the market.
This means that who purchased them at the time could still be using them, but someone who wants them now will need to look for alternatives.
But, of course, someone on Typophile could want to sell you their license. Or know some old software bundle you still can hunt on eBay.
For that, I’m sorry, I cannot help.