Sounds like western WA or area with similar conditions. European types tend to have an upright tree habit, with firm-fleshed fruit that is free stone, often used for drying and canning. ⢠Early Laxton�"Ripe mid to late July. Yellow skin, blushed pinkish orange, yellow flesh, dense, sweet, fruit small. Productive, with spreading habit well suited to home gardens; vigorous tree. ⢠Imperial Epineuse�"Ripe late July to mid August. Purple-blue skin, greenish yellow flesh, excellent flavor, fruit medium size, productive, reliable. ⢠Early Italian types (Richardsâ Early)�" Ripe mid to late August. Blue skin, greenish yellow to yellow flesh, medium or slightly below in size, dense sweet flesh, suited for both drying and canning as well as fresh. Most Italian prune types do well in western Washington, though some may need thinning if they set too heavily. ⢠Mirabelle, Geneva Mirabelle�"Ripe late August to early September. Yellow speckled skin, yellow flesh, small, round, and sweet. Classic variety often used for culinary (tarts, jam), very productive and reliable, well suited to backyard gardens. ⢠Seneca�"Ripe mid August to early September. Reddish purple skin, yellow flesh, fruit large, completely free stone, high quality, either eaten fresh or used for drying and canning. ⢠Victory�"Ripe late August to mid September. Blue skin, greenish yellow flesh, fruits medium large, dense, sweet, very productive, upright growth habit. Tree habit with large fruit, very ornamental. ⢠Victoria�" Ripe early to mid September. Well known English variety. Purple-blue skin, yellow flesh, medium size, flavorful, productive; fruit usually needs thinning. ⢠Valor�"Ripe mid September. Blue skin, yellow flesh, medium size, good flavor, reliable and productive. ⢠Stanley�"Ripe mid September. Blue skin, yellow flesh, medium size, uniform, good flavor. An old standard for late season prune plums Here is a link that might be useful: Fruit Handbook for Western Washington

In humid climates European plums get infection a lot more than Asian plums. So Asian plum trees are easier to grow. I have Several European plum trees that are young and many grafts. I like Oullins. Oullins is an old Green Gage seedling. Oullins gets a lot larger than Green Gage. Oullins stays green and fools the birds from taking them when they get ripe.

Apricots usually live a long time in west Texas if watered regularly. Some are dying here now but those are ones without irrigation and ~5 inches rain in 22 months. An apricot here could easily see 30 years. Around Brownwood probably somewhat less but still quit a long time. Sour cherries would likely be about like European plums. But for both rootstock could be the deciding factor.

I do not recommend it. You may get a delayed incompatability. About the time you get a good fruit set, if at all, the branch will break off. Better to graft Europeans on to Europeans. Even if it did work, the vigor is not the same. I lost two Puget Gold Apricots from Graft Incompatability. The Nursery used some prunus root that worked 'for a while'. Here is a link that might be useful: Home Orchard Society