The 'Wickson Challenge' ... lost out

'Wickson Challenge' Plum

 This painting has a very faint writing on it - 'Wickson Challenge.' 

If you look that name up you find that 'Wickson Challenge' was renamed 'Formosa' and is a Burbank variety. So is this variety still around? And can you buy it?

The plum was front page news in the January 17, 1907 Pacific Rural Press and California Fruit Bulletin.