My working knowledge of LTs is obviously limited and when I saw you were looking for a KB my mind went straight to all those I see in places like Thrift Stores (...them and old mice) rather than 'parts' for a keyboard.
Now, given that your unit is so new, it would seem to me that unless you can contact someone at the Sony Service Center inquiring as to specific replacement parts, you may be out of luck.
Then again, that would depend on both who supplies the parts to the assembly plant and if they are available as replacement parts...or whole assemblies only.
As for this forum...
I was kinda surprised when I saw the 'System' note on return. Then again, this is the first thread I've posted to in four months.