Believe it or not Eric is a madman and made all those himself.
Knowing the source of the TMNT Portrait images would already help me a lot
Bad news and good news!
bad news is, no idea the source on those!
I released all my large ports literally yesterday in this thread here:
Including the large version on those turtle ports. they are 240x280 and png, so just use them or convert them as you like. In the folder I also included the small ports too. they are .png as well though, so you need to use either mugen 1.1 or convert them to pcx. (fairly certain a reverse image search on the turtles will bring up the source too)
Double good news! So like 5 minutes after I posted this I thought... wait I wonder if I still have the work files for the turtles. and I do! No krang or shredder though. They are forever lost to the recycle bin I'm afraid. leaving the rest of the post as is in case anyone else wants the small ports.
Spoiler tagged cause they are like BIG
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