I used their existing images to create the Instagram and IMDb images I use on ryanjohnsonactor.info.
I should probably have shunted all of that into a child theme, but I didn’t (and it’s been running for two years, so why mess with it?).
http://deirdre.net/pinboard-wordpress-theme-icons-for-instagram-imdb/
If you change the 2x links from .png to .psd, the Photoshop files I used are there for the grabbing.
Hope this helps,
Deirdre