Hi John -- sorry to be slow in responding. I am also a Brull descendant, and I'm the one who did a relatively comprehensive research study on all of the Jewish families of Prostejov. The 1857 is online through badatelna -- it's a part of the Moravian familiant collection. However, if there is something that doesn't tie together here, I'm probably the one who made the error. Email me at robertbhanscom@gmail.com, and I will try and sort this out. I do remember, when I did my research study, there was some confusion between the Brull family of Prostejov and the Brull family that lived in Gewitsch.
Looking forward to hearing from you.
Best regards,
Bob Hanscom
Andover, MA