I'm the last person who should be offering an answer to this question but I think it would be impossible to find the compound for making 78s.  Every company had a different formula for their records and the material, (which certainly wasn't pure shellac), was manufactured in huge quantities so to find a formula for producing a small quantity to make a record I would say is impossible.  There have been a few 78s manufactured recently, but every one I know of from the last 50 years was produced on vinyl and I believe all recent ones have been designed to use a microgroove stylus, (very confusing when I put the recently produced "Good Vibrations" 78 on my Credenza and wonder what needle to use - soft? medium? or loud?)
db 

    On Tuesday, February 9, 2016 10:52 AM, Tore Simonsen <[log in to unmask]> wrote:
 

 Dear list,

do you know of any record plant today who is capable of making shellac 78 rpm records? I have a musician friend who is asking me to find this out; she is serious about it! I understand that it is possible to find mastering studios for the 78 rpm speed, but shellac pressings??

Tore Simonsen

Professor Emeritus
Norwegian Academy of Music

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