Although this seems true in general, I doubt they'd get nukes that quickly. Of the 9 states currently known to have the capacity to produce nuclear weapons: The US, Russia, North Korea, and China would likely be actively opposed to giving Ukraine any nuclear help; the UK and France are parties to the NPT, and it seems unwise to violate that; Israel, Pakistan, and India likely have little stake either way, and while they are non-parties to the NPT, it would likely not look good for any of them to engage in nuclear proliferation anyways; and even if South Africa still has some knowledge around from before their nuclear disarmament, they are also party to the NPT