This rifle is no Haenel, neither a Modell 1900 nor a 1909. It lacks all the earmarks of the Haenel models: there is no gas flange on the cocking piece.
The bolt stop / ejector is of the standard M88 design.
The flush magazine is too narrow to be of staggered design, so it is single file, about 2 shots.
Here are (again) two photos of Haenel actions for comparision, M1900 on top and M1909 bottom.

Perhaps someone can post the corresponding auction photos?
IMHO it is a custom rifle on a standard M88 action, modified with a flush magazine, shotgun style triggerguard and ds trigger. As "Hubertus" was the trademark of the Immanuel Meffert company, Steinweg 22, Suhl, the rifle was built by that gunmaker.
BTW, the "25-35" 6.5x52 rimless cartidge, DWM case # 519A,mentioned in the catalog is better known as the .25 Remington. The .25-35 Winchester aka 6.5x52R was case # 519.