How about Renaissance?
or, sure to please Carl,
Salzedo
Method
Lawrence
or
ala Zlatkovsky
or
Harponthese
Harptonics
MightyTone
etc.
However, if there were a manufacturer apart from the brands, perhaps I should go to them. Perhaps that is why they suggested I contact D’Addario. If they would use a different material than usual, then it might work out, I guess.