Home Guy wrote:
Glass blocks (for privacy or decorative walls and window openings) are
usually 3" and 4" wide.
....

What I can't find is any evidence that anyone is making / selling 2"
glass blocks (any size, 6" x 6", 8" x 8", etc) individually (or in the
typical box-quantity of 4, 8, etc).

So - are 2" glass blocks available to the home-owner / renovator?

It doesn't appear so, no.

I'd think owing to the thickness being only 2" they wouldn't be nearly
so stable as the 3- or 4-inch blocks that stack so there's probably not
much market for them as a free-standing product outside the bound window
use. (Which I hadn't seen before, but repeating similar search as to
what you've already done, that would be my take on the results...)

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