I need hundreds of rounded 50x50 images of famous figures

I run an online forum, and a recent addition has been a system of virtual 'trading cards' our users receive from packs they purchase with our virtual currency (not real money). All images used must be circular, with the rest of the image being transparent. The whole image doesn't need to be transparent - just the outside of the circle. Dimensions should be 50x50. See attached files for reference.

The list of figures needed is also attached. Please only use images that are licensed for re-use.

This is quite a long job but it is very easy - all you need is GIMP.