Relax guys; it's OK.
The Ruger 38/357 revolvers were identical in every respect except for what Ruger chambered the identical cylinders in and marked on the bbl. Other revolvers may have been different in size, materials, and metallurgy, but not the Rugers.
As far as pressures, the 9mm they also chambered in the same cylinder/frame matches the 357 Mag pressures, and in the case of 9mm NATO, exceeds it by as much as 20%.
Already got a Service Six in 357 Magnum BTW.