Jim. You can order 40 YEARS WITH THE 45-70 by Paul Matthews at: (www.riflemagazine.com). The order number is #567.1. Price is $14.50 plus S&H.
That'll make it easier to track down.
BTW. my suggestions for micro-Groove barrels will work with the ballard style too.
I do the same thing with 30-30's and I have Winchesters and Marlins with MG barrels.