Does anyone know of a source for original-manufacture Burke and James ground glass?

I need to replace a cracked 4x5 ground glass on a Burke and James Rembrandt Portrait Camera I. The ground glass measures 4 3/16 x 5 1/4" is .048 inches thick (1.219mm). It has the following lettering along the long side of the glass: BURKE AND JAMES, INC CHICAGO MADE IN USA.

The grid lines and the lettering appear clear(ish) compared to the frosted glass and seem as if the glass itself was acid-etched with some sort of resist -though, I am not sure how the manufacturing of glass like this would be done in a production setting. I'd like to hear if anyone knows how this type of production was done.
But mainly, I am hoping someone knows who has some of these original B and J ground glasses still kicking around and is just waiting for me to get in touch with them.

Here are a couple of photographs of the broken glass I am trying to replace:
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