I recently bought a antique herters 12 ga press and its missing the plastic plate to hold the shells correctly anyone know of a place I could buy a new one?

I'd suggest joining this forum and asking the guys on the reloading section.. Some good guys, very knowledgeable
https://www.shotgunworld.com/

thanks

www.thehighroad.org

Maybe here

Does the press look anything like this old Texan? If so, might be others that would fit.



Also, if memory serves, Herters didn't make anything themselves.....but mostly marketed products made for them by others. I have a Herter's bullet puller that was made for them by Forster. Perhaps if you knew who made the press, a base plate would be easier to find.

the press looks like a older mec

Ebay.com

Most anything MEC is still available, most likely just sports a Herters tag.. many of the replacements I’ve bought and have on hand just in case someday they quit making them. Love my MEC’s and cheap replacement parts is a bonus.

Herter's didn't make their own reloading stuff, they just took other makes and re-badged it Herter's. BUT, most of it was good stuff. I've got an old bullet sizer that is identical to a Saeco sizer of the day and the name 'Herter's' is cast into the body.
SO, what ever you have was made by a a known reloading manufacturer of the day. Herter's went out in 1976. Look at old pictures and figure out who made it for Herter's and you should be able to get parts for it.