Interesting question.

I am not familiar with the RSM Stuka kit you mentioned, but I assume it is more of a semi scale version of the Stuka than a full scale replica.  Given that semi scale models that are designed for stunt will likely have outsized wings compared to the fuselage as far as scale dimensions go.  So, to get a pilot that is appropriately sized to match the fuselage, let's compare the length of the model fuselage, 29 in, to the full size Junkers Ju 87G-1 Stuka fuselage which is 37 ft, 8 in, including the spinner.  So assuming the spinner is just over 2 ft long (based on a proportional measurement from some 3-views) the full size Stuka fuselage is just over 35 feet (from spinner back plate to rear of tail) to compare with your   29 in dimension.  That means the scale of your kit model is approximately 1in = 1.2ft, or somewhere between 1/14th to 1/15th full size.  So, a scale pilot, assuming a pilot of 6 ft (or slightly less), you would want a pilot for your Stuka to be approximately 5in tall or slightly less.  If you are looking for just a pilot's head or bust, you need to find one that is slightly more than 3/4" = 1' scale which is 1/16 full size.  Good luck.

    Thank you Keith.....Now I go searching.......
Hope this helps.

Keith