By no means the full list but, if confirmed as a flaperon from a T7, nothing I saw in the link below that suggests the possibility it came from anything other than MH370.
Incidents for aircraft type Boeing 777-200 | AeroInside
EDIT: And, I'd love to head out there and help beachcomb but funds say otherwise. The only idea I have is to hide in a container in Felixstowe and when found admit that I'm a stowaway from Mauritius in the hope that I'm sent back...