If Weserübung Sud 9. april, it should be found between the units I list under here. I late April, It could be others, but most pic. from april 1940 DK are from the first period. I dont know how see the difference but maybe the names of the units can bring you further. If in West, it would proberly not be the from the 729 Schw. Art Abt. while they were following the german Attackgroup A. -East -Jutland. I think you should start loking at the 677. AR, 240 AR, or the 13. compagny of 399. IR and 401 IR ( Both 170 I.D. ) ..I also think you most proberly should find your model between older models from Germany ww1 or even more proberly models taken by Germany by the Chekoslovakian takeover.
170 I.D. artillery
-240. AR ( Proberly type I Lh 16 105mm )
- 13. Compagny (Proberly with 6 horsetowed 75 mm )
729 Schw. Art. Abt. (Mot) with II+III battery ( 105 mm )
3. Abt./ 677. AR (mot) with ( 3 batteries with light haubits )
Maybe they are German 7,7 cm Feldkanone 16 n.A., converted to 7,5 cm.
Above guns are a Danish 75 mm feltkanon h.S.K. M. 1902 - 128 pieces imported from Krupp in Germany before WWI and 96 are still used by front line units in April 1940.