Somewhat interesting story behind these 2" glass blocks.
Seems that Pittsburgh Corning was the maker of 2" glass blocks in north america, and as I mentioned in my original post they were the spark behind a product line of pre-fab windows that were offered by window companies back around 2004 / 2005. If anyone else has been making 2" glass blocks in NA either before or after 2004, I can find no info about it.
Individual window companies offered custom-built window units using the Corning blocks and various interconnecting frames and lattice accessories made by Corning (along with lots of silicone used as grouting). These were offered under such brand names as "LightWise" and "Hy Lite" by regional window companies serving local markets.
As I was unable to locate any local wholesaler/retailer selling 2" blocks, I contacted some of the window makers I found on the net that seemed to be making these 2" block window units - one of them being Pacific Accent (which was somewhat difficult to contact since the toll-free number they list doesn't work from Canada, and I wasn't able to find any working toll-number for them on the net).
The story is this:
Pittsburgh Corning sold 2" glass blocks to window companies under contractual contracts that the window companies were only to sell them to end customers as part of finished window units, and not as individual (unassembled) blocks. The reason being that Corning did not want to take on the legal liability as a maker/supplier of these blocks if they were used by contractors, masons (etc) to make conventional glass wall or partial wall structures. If contractors could not realistically or "legally" get their hands on the glass blocks (separately, in boxes, etc) then Corning would have faced little or no liability risk from the event that a wall or structure made from these 2" blocks would fall or topple and injure someone.
Apparently Corning internal risk management came to the conclusion that while 3" and 4" wide glass blocks can be built into free-standing or minimally-supported walls or other structures, the 2" glass blocks can't. Hence their limited and controlled availability ONLY to window makers for use in pre-fab framed window units.
And even that wasn't safe or lucrative enough for Corning. I called Pittsburg Corning and was told they no longer make the 2" glass blocks (as of when - I don't know. Possibly several years).
But there is apparently enough of a demand that some window makers are sourcing them from Europe, via Glashaus Inc (Crystal Lake, Il) which is the North American distributor for Weck Glass Blocks.
Weck was originally a German glass block company, but was bought a few years ago by Seves - which (I believe) is an Italian company and which I'm told has been buying many or most of the major European glass block manufacturing companies.
The web-sites
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and
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are identical, and from their products you can see that they do offer 3 of their 8" x 8" blocks in the 2" wide format (technically, this is under their Metric product line, where the blocks are 190 x 190 x 50 mm in size).
It still might be the case that the availability of these 2" glass blocks might be limited to window companies - or at the very least kept out of the normal building-products retail chain (hence you won't see them at Lowes, Home Depot, etc).
Glashaus lists their US and Canadian retail distributors, and so I will be following up with the closest retailer to look into buying what I need.
I hope this information is useful for the readers of alt.home.repair and misc.consumers.house.