i have talked to friend, a lockcollector from suisse,
he thinks it is from the end of 18. century,
but it is very difficult to date without a look inside.
it seems it consists of two different parts,
the oblong part and the baroque part.
maybe this two parts were merged sometime.
he dont know a lock like this.
key must be between last quarter 18th cent. and first quarter 19th cent.