If you're talking between the .22 LR and .38 Special, there's not much. Even finding on-the-shelf ammo for the various .32 revolver cartridges is a challenge. .22 Mag in the North American Arms tiny revolvers, Heritage Arms convertible cylinder models are current, but I don't know if Ruger still does the same.
The various ".32's" over the years varied between proprietary cartridges - .32 S&W short,% long, Colt "new Police", .32 Colt, etc. but no more. At one time, the .32 was popular with Rapid Fire Bullseye shooters over the .38 Special due to reduced recoil, but that died long ago.