Don't get caught out by paint finishes on current restorations or airworthy warbirds. Most owner/operators will try to be as authentic as possible, but the longevity of their precious airframe is more important than some paint details, therefore some, such as prop blades, may employ a more resilient, 'modern' surface coating, often in gloss rather than matt.
In WW2, 'allied' prop blades were mostly matt black, in order to reduce glare from the spinning prop arc ( a possible compromise of the camouflage effect from sun 'glint') and prevent dazzle to the pilot. Also, certainly on 'Jablo' -type wooden props, the 'black' was actually a membrane of a rubber material, to assist with the above and prevent moisture penetration of the wooden blades. This, when new, was semi-matt black, but quickly degenerated to more of a 'tyre colour' , more very dark grey than black.