Dirk -- phantastic pieces -- thanks for showing!
I just love Nr. 3; that's the Ikora style I am most fond of.
I think this could be PN 34/2640, shown in the 1928 catalogue (and in the hand-coloured catalogue as well). Size 25.5 cm, so that would fit...
Nr. 4 is very nice, too -- and definately Ikora; the shape is in the 1928 catalogue as well, PN 104 (with two different decor numbers; height is given as 13 cm, so a perfect match).
Michael