Great question.
Unfortunately we can be 100% certain that any neck dimensions that deviate from YJ's 1959/1960 vintage template (43mm nut) or the 1962/1964 J-bass alternative (38mm nut width) will never be made, the vintage radius included.
The reason is five-fold, and is a great opportunity to being up a little of the "Moollon why", since it comes up fairly often in email and DM's, and will probably continue to...Note just as importantly that a number of the following can also be applied to why YJ is insistent on not taking custom requests or adding additional options: (1) YJ really likes the "collective perfection" of the every aspect of the models put out in those years (unintentional quirks and all) that most certainly includes the neck profile and nut width, such necks being (2) a comfortable size for most people both new to vintage-reproduction-minded builds like Moollons as well as most hands in general, (3) YJ wanting consistency with as little surprises on the used market as possible, (4) talk of certain Moollon special accommodations made in the early years being brought up during the ordering process as if they were normal options, the immediate impact being (5) overwhelmed as a luthier, since he is the unassisted entirety of Moollon working without CNC machines, not to mention any assisting pickup winders or in-house tech folks, etc. Just as necks and bodies are done by YJ in batches in order to streamline a collective workforce, you can imagine how adding just one more neck option would complicate things all the more, especially since each hand-shaped neck needs to be a 1:1 match to a body without being too tight or with any predictable gap forming as the bass adjusts to its new home...yet another point of concern, since nitrocellulose lacquer doesn't have the "freezing power" that a thick and solid polyurethane shell can provide to assist in the overall rigidity of the neck pocket/gap.
tl;dr there's a whole lot going on at the Moollon shop for one single dood to handle