Your odds will certainly be better with self pollination, but would that matter? Who knows... There are no completely solid rules in nature.
That kind of sparse, irregular variegation sometimes recedes in woody plants with age. After 5, 10, 15 years, it may disappear (or not). Even if your odds quadruple, say, from one in 10,000 to one in 2500, would that be advantageous for you? On the far less likely other hand, it might produce seedling variegation abundantly. Unless you can ferret out those who have tried such an experiment, and it's likely that many people already have, only your own results will tell. A fun project, for sure, although very long termed.
By the way, sports are genetic, just in a different way than seeds. Either of them may or may not be stable.
