Ruger single Action grip id , help and assitance.

[happy]

hi guys , can use your assistance , below are two Ruger Single Action grips the grips on the left is unknown ?

the grips on the right are marked RR for a Ruger Single Six, Blackhawk revolvers with XR 3 on the butt.

, can you please help me Id the grips on the left as they are larger grip frame than the grips on the left .

many thanks, happy

 

[48flyer]

My guess would be the grips on the right are for a Super Blackhawk, but I personally couldn't imagine putting bigger grips on one.