Why would you want to change the size? The 10R22.5 is a widely used size on commercial trucks & trailers, so it generally very competitive priced and readily available wherever you may be. Most of the major ire manufacturers offer that size too.
The nearest metric size is 295/80R22.5 and that should fit nicely. Gives a bit more load carrying capacity too, but probably will cost you 25% more per tire. And few tire dealers will have a 295/80 in stock, so it's always a special order from the warehouse.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL