The average height of a British man born in 1920 (so about age 20 during WW2) was 5'8"/173 cm, so the models should be about 2.4cm for that era. Sailors of 5'5" would have been around. I served with men of all sizes and some parades were very diverse in body size in the corps.
If you want to be really pedantic about scale. A person's height is measured when they are stood bolt upright, a person going about their job is not bolt upright. A flat cap beret could add 1/2" to a persons height, a beret with a peak folded above a cap badge could add 1", a peaked cap (cocked at an angle) could add up to 2" (Soviet 4"). Like I said, pedantic. One thing you would not see in a working unit is uniform sizes.
Scale figures can cause even more problems for historic models, as people in the 18th and 19th century were much smaller, especially considering the number of young boys that went to sea. Personally I gave up looking for small enough figures. It seems like a lot of manufacturers assume modelers want 6ft figures.