I don't think Logees carries this species any more, and I have not come across it in cultivation in the US in many years, though I suppose it could exist in some California or Florida garden/nursery. It is evidently still in cultivation in glasshouses in the UK, and perhaps other European nations. It would be difficult, if not impossible with current nightmarish bureaucratic craziness to get more stock from Africa. This is due in large part to the Convention on Biodiversity, a well meant but seriously flawed attempt to conserve the world's biodiversity. This treaty will basically doom many plants to extinction by making their export to other nations legally very difficult or impossible, so they will die when global climate change and habitat destruction take them out in their native ranges. Add to this the increasing difficulty and ever more restrictive regulations coming down the pike for importing plants into the USA, and it becomes easy to see why serious horticulturalists need to make better use of their refrigerators as seed banks. In my experience, seeds of many sorts can be stored in simple paper envelopes (I use either coin or stamp envelopes) in the refrigerator for over a decade, perhaps much longer (haven't had many more than 15 years). I understand that seeds can also be frozen, but I worry about the kind of damage (freezer burn) that appears on frozen food that has been stored too long, though I imagine that storing them in sealed containers with desiccant might help. Plus I don't have to worry about potential damage from thawing every time I open the door or a power outage occurs, and I am not concerned with storing them centuries beyond my lifetime, after all I won't be worrying about it then! I do wish I had realized the benefits of cold storage of seeds before, as there are a few pelargonium species I had during my research days at Cornell that I set seed on, but that I lost when the seed got too old to regenerate after a few years at room temperature.
Another nice aspect of storing seeds is that one can grow several kinds of unusual/commercially scarce or unavailable annuals in a limited area by skipping years, simply save the seed one year, stash it in the fridge, and grow something else in its place for a few years, then start some stored seeds of that annual again a few years later. It also is a means of conservation on a very basic level, which is something worthwhile in my view, despite all the imperfections. True, a botanical garden or government administered seed bank with wild collected samples is best, but that won't happen to the necessary degree it needs to happen. Academic criticisms such as the use of garden seed that is not documented wild source, possible hybridization, and inadvertent selection for garden conditions have a degree of validity, but IMHO conservation scientists obsess over these details too much while the forests and savannas of the world burn faster and climate change accelerates more quickly they are capable of responding to in any meaningful fashion. So lets do our part, however small, to conserve at least a few species and unusual selections of the wonderful flora our planet bequeathed us with, so that future gardeners might have a chance to enjoy some of the flowers that thrilled us in our lifetimes and that might not otherwise have continued their existence without our help.