Ed and guys.....
Do not worry so.
It is in regular production and after a bit of searching on Google if nowhere else, you can find it in micro-seconds for sale, fresh on shelves all around the place.
If the local hardware or artists supply stores don't have it, you can order it from the online hobby shops or even Amazon.com
The guy on eBay overpaid, those same tubes sell for a bit over $3 each today from online sources.
When the topic came up a day or so ago, I looked online and found it easily in a great many places. It's also in most of the hardware stores and artist supply stores around me as well as in the hobby shops.
A box (12 tubes) of Ambroid cement sold for $133 on ebay. Guess I'm not the only one who misses it,