Being an older rifle, I would expect that the barrel hole was drilled straight. You can test by clamping the receiver to a perfectly flat table top and measuring the distance from the table to the near edge of the muzzle; then flip it over and measure again. The difference, if any, will be 2x the deviation of the barrel from straight.
Is it possible that you installed the front sight with a cant? A set of scope levels, one on the bolt and the other on top of the front sight ears, will tell you that.
If your barrel is crooked, I wonder if Ruger CS would take it after 33 years? If not, you may need to have a gunsmith adjust it. Connecticut Precision Chambering does this but only with their full tune-up service, which costs a bit. The hole in the receiver is re-drilled straight, and the barrel shank is cut, a new extractor slot is cut, and a new shoulder machined on a lathe to fit the hole perfectly. I also think it's possible to re-drill the hole and install a shim for the unmodified barrel to fit - as is done with the Takedown. But I'm not a gunsmith.