These were inexpensive western-style single actions imported into the USA in the later 1950s through the 1960s (until the '68 GCA I believe). They were built in West Germany by J. P Sauer & Son. There should be a rollmark to that effect.
They were imported by several companies, one of which was Hawes. They came in several of the popular calibers of the day, .38 Spl, .45 Colt and .22, among others.
The .22 version also came in two frame sizes, a smaller .22-only frame and in a large frame version (centerfire version) with a permanent subcaliber barrel installed. Most of the ones I've seen had plastic stocks that resembled stag, though I have seen wood stocks also.
Value on these historically has not been very high ($100 - 150) though Cowboy Action Shooting has raised the prices a bit in the last couple of years.
There have been several discussions on these revolvers here on TFL. If you use the search feature you'll find more information.
