Actually, the RTP already provides upper-body pictures for some of them, look:
But not for all of them, as you can see, some of them miss their upper-body picture...
I have a folder *called* extra assets in my DLC folder, but it has one subfolder containing music and other subfolder containing only the first 8 of those. Nevermind. I looked again and the others are also there. Either they got added back in during one of my occasional file integrity checks or I just misremembered.