OK, problem solved.
Should I admit that I just screwed up loading w .595" first time, but now Lo & Behold the readily available (from Track, &c) .595 works just fine in my Caywood French Type D? Nah.
Meantime here is what I learned.
Per C. Wallingford, Ray Pine's address is: Rapine Bullet Molds LLC, 9503 Landis Lane, East Greenville, PA 18041. Guessed & sent $3 for a catalog. Should find out one of these days if he is still in business.
A guy in Europe, Miha Previa,
www.mp.molds.com, makes fine brass molds w attached sprue cutter, will make "custom" round ball sizes for group orders of 5 or more. Stocks various rifle bullet moulds. This thanks to Square Butte (who corrected me when I pronounced it Butt). Hopefully I am on the list for a .585. Don't suppose I really need it now but I feel one just can't have too many round ball mould sizes.
NEI, whoever they are, are said to have round ball moulds. Haven't investigated yet.
Dixie no longer has a big range of ball sizes in their "scissors" molds. By the way, my more ancient Dixie catalogs say the castings for those molds were orignally made to be heated, for ironing out one's very curly hair, to straighten it.
Buffalo has bp cartridge rifle moulds, not balls.
And, of course, Mr. Ray Pine makes those Rapine moulds.
Thanks to everyone.