Many thanks for your helpfull and appreciated information! You are right, there is a R on the lever boss and the 99 has a Monte Carlo stock.
The cocking indicator spring is ok, but the cocking indicator is broken at the drilling were the spring is going through. That is not a big problem - I can make a new indicator pin.
Unfortunately the owner is asking for 900 € for the rifle, in my opinion to much for the gun in that condition.