Made by Herbert Schmidt of West Germany around the 1980's.
Seems like a fun little thing one went on auction in 2022 for $1750CAD in working condition.
Looks like the rifles were pretty rare but a gunsmith might have parts off a donor handgun.
At the end of the day it comes down to if you want to shoot it and cost to repair, a new SAA rough rider revolving carbine is only around $500, if its not a simple fix you might find yourself halfway to a new rifle by the time you get it repaired.