Give Paul @ KY Imports a call.. 502-244-4400
IIRC He had the OE set of grips for Centennial #248 in his stash..
I had bought the revolver & later found a set on this forum..
Later when I stopped bye He had the grips in his case..
Bet He still has them.. Worth a try..
I just found a checkered set online for $140 Googled "Centennial High Horn Grips"