The webbing equipment is 1908 pattern, and the Airfix/HaT figures do not have that. The WW1 Canadians do have that, but they have gas mask bags which you do not want. I would suggest use the Airfix/HaT figures and use putty to correct the webbing equipment.
The bandoliers are cavalry or artillery equipment (1903 pattern). HaT have not released the British Cavalry yet, but 5 figures in the Airfix/HaT artillery set have these bandoliers. Or you could make them with putty. Some soldiers have cavalry boots as well: again, use putty.