OJ population by pose varies significantly and is best discussed by first understanding to which years/subsets the pose belongs. George Myers, for example, has three poses as follows:
337-1 Bat at ready, looking at camera = Issued 1887 (type A & B), 1888 (Fb), & 1889 (Fc)
337-2 Stooping, hands waist high = Issued 1887 (type A & B) & 1888 (Fb)
337-3 Tagging player on ground = Issued 1888 (Fb)
John's estimate is certainly in the ball park but suspect George Myers is an easier subject with closer to 100 copies pose 1, 70 copies pose 2, and 15 copies pose 3. This is merely a guess and reserve the right to answer differently next time.
Pose population is far from normal distribution. While 1887 cards, for example, are generally easy there are many outliers (Madden "bat against rock" for example
)