Little plastic thingy on door seal

[M1AGM]

I am in the process of resolving a window rattle and have removed the door card. I noticed that there is a plastic grommet type thingy missing from this hole:



Can anyone advise what part it is and where I can get one. I think it is one of those long plastic dome ended stud thingys, probably the same as the 2 other ones in the side of the weather seal to the left of it, is it a generic part?