keyboard replacement

Unfortunately the silicon cup/nipple on the right arrow key appears to be missing, so there is no easy way to fix it except to replace the entire Keyboard which requires replacing the entire Top Case Assembly.

If you had access to another broken keyboard for that model, it is possible to snip the plastic holding the silicon cup/nipple from the bad keyboard and superglue it to the other keyboard (must make sure to properly align it and use minimal amount of glue on the plastic tabs).

A broken keyboard can also give you the scissor mechanism and key caps needed. However, you must make sure to get the exact scissor/key cap to match your laptop's scissor & key cap type. Generally there are two different types for each specific model laptop. Unfortunately the different types are nearly identical and extremely hard to tell apart. Many times the center area of the scissor mechanism is how you tell them apart...one has a full circle as in your picture, while another generally has a small cutout in the circle on one section, but that may not always be the case.

You don't mention the exact model of your laptop, but if the battery is glued into the underside of the Top Case Assembly (beneath the Trackpad & Palmrest), then if the battery needs replaced (showing an error or "Service Recommended" condition), then you can replace the battery which will also give you a new Top Case Assembly for the battery only price....just make sure to have a Battery replacement and don't mention the key issue so you get a discounted battery only repair price (part will be considered damaged, but that should be Ok). Some MBAirs do have a replaceable battery on some models even if they are glued so this battery repair trick won't work for some models.