Normally when an option like that doesn't show up it means that it is temporarily out of stock. A good way to check and verify this is to look at another one of the same hilts red or blue hilts and see if it comes up in the options if it does than it is just out of stock in that color. Hope this is helpful.
The option doesn’t show up at all. Not listed in the emitters section or on the build page for the hilt itself.