This is something you can do in the meantime. I added this and I really like it. I glued it to the underside of the lid with two part epoxy. One of the reviews on there is from someone who added it to a 13.5 too. They added two instead of replacing the stock light.
( if you are interested in this light, the Amazon description says that it has both white and blue LEDs, but it is all blue LEDs)
Very interesting. I’m checking it out. Thanks!