Among a group of recently acquired Telektra rolls is No. 80563,
"There's a Little Spark of Love Still Burning", by Fred Fischer.
I finally deciphered the signature of the pianist on the box
label and it is Phil Schwartz. Here is a scan of the box label:
https://www.mmdigest.com/Attachments/24/07/26/240726_183757_Phil%2 

The "27 1/2" in the upper left corner of the box label is a price
code, "$2.75". According to the inflation calculator at the
website for the Federal Reserve Bank of Minneapolis, that amounts
to $79.46 in todays U.S. dollars.

I see Phil Schwartz was a fairly prolific ragtime composer but
I can't find any biographical information on him. It looks like
he was an accompanist to singer Ruth Etting:

https://www.youtube.com/watch?v=aEM0o-sE7xY (Ramona)
https://www.youtube.com/watch?v=6XWDnsxm6Do (Say 'Yes' Today)

Some of the music compositions of Phil Schwartz are listed here:
https://billsaudioreferencelibrary.com/phil-schwartz 

Does anyone know the story of Phil Schwartz?

Thanks,

Dave Krall
Hammond, Indiana