The problems were with hot 125 grain loads used by the cops.
IMO: Back in the day, they would shoot a lot of .38 Special lead bullet ammo at the range, then shoot a few cylinders of hot magnums they carried without cleaning the lead out of the forcing cone first.
Cracked forcing cones were the result.
Prior to the invention of JHP ammo in the 70's, factory .357 ammo was loaded with a 158 grain soft-swaged bullet that would lead the bore severely in six shots. That also increased pressure when switching to jacketed ammo without cleaning the lead out first.
Another factor was that .357 mag ammo was loaded hotter by the factories then. The SAAMI pressure limit was reduced 5,000 PSI a few years ago.
I have a 6" Model 19 I bought in 1970, and a slightly later 4" Model 66. I shoot nothing but hot .38 Special handloads, and 140 grain .357 Mag handloads, and they have shown no signs of the slightest problem.
I would say that if you can afford to buy enough screaming hot .357 ammo to wear out a Model 65, you can also afford to junk it and buy another one.
If it's truly "like new" for $350, I would get it while the gett'ns good.
rc