GG: Last Three Discs in the Glenn Gould Edition?

[Charlie Siffermann <charlie@swlink.net>]

Upon Reading that the Last Three Recordings in the GG Edition are being
issued in early March, I am curious about other recordings.

In the Discography of Glenn Gould:  Music & Mind, it includes: 

A Record by Hallmark (RS-3) from 1953, that lists Glenn Gould
accompanied by Albert Pratz on Violin;  playing transcriptions from
Prokofiev, Shostakovich, and Taneieff.

Does anyone know anything about this recording, the accompaning
violinist, etc.  

After hearing about a concert recording, GG made in Baltimore; does
anyone know of other concert recordings he made, which are not currently
part of the GG Edition?  

And finally, are any other companies, besides Sony, currently issuing GG
recordings?  

All the Best,
Charlie