What kind of shoulder buttons do I need to fix this?

Seeing as this thing wasn’t released en masse in the US, I feel like I’m stranded when it comes to fixing it.

I’ve found n3DS XL replacement shoulder flex cables that supposedly work for the n3DS but I can’t find any legitimacy to the claims and I don’t want to delve into this until I’m sure I’m buying the right thing.

Also what is the shoulder button assembly like on an n3DS? Once again I feel without any guidance due to lack of widespread availability on this side of the Atlantic (and I haven’t found many Europeans tearing down their n3DSes).