Yes. That one likely shipped in 1958. It is a fairly early model marked K-38 Masterpiece. The earliest model marked K target revolver I've found so far had serial number K316819 and was a Model 19, shipped in 1958. The earliest K-22 marked as Model 17 was in the K326xxx range, and it shipped in November, 1958. K327xxx was also a Model 17 and it shipped in June, 1958. (Note how out of order these are.)
Of course, only a letter can tell you for certain when your revolver left the factory. But you are on solid ground in suspecting it was a 1958 shipment.
Nice looking K-38. As you assumed, the stocks are from 1978 or later.