Best left to a gunsmith
Colt did not make the rifle. Sauer made it for them.
Try e-gunparts.com
Try want ads, gun shows, gun shops.
Colt. That is a Colt Colteer 1-22.
I believe it's a Colt ( Colteer ) Semi or Bolt
What is the age of a Colt rifle serial SLD25319
You will have to call COLT to find out.
A shotgun is a firearm. A revolver is a firearm. A pistol is a firearm. A rifle is a firearm. If you want even more specific -- A Remington 1187 is a firearm (shotgun). A Smith and Wesson 686 is a firearm (revolver). A Sig Sauer P226 is a firearm (pistol). A Colt 6920 is a firearm (rifle).
a gunsmith needs to check both the ammo and rifle.
What kind of rifle is it? Bolt action, semi-auto? Caliber? Does it have the original box, manual, papers? Any accessories? How many rounds through it? Finish?
It was a Colt rifle produced in 1957 selling for 129.95 at the time in 30.06 or .243 cal.