I was gonna tell you I had a Tyler T-Grip that I took off my Diamondback you could buy. Since Dfariswheel said your gun was made in 1922, it will not work. They are made for guns after 1941. You might find something at their website. For your reference since I already had copied this from their site to put in my ad;
"Tyler's T-Grip #5
For Colt "D" frame Round or Square Butt models. Agent, Cobra, Detective Special, Diamondback, Police Positive made after 1941, with standard size grips."