Answer: Prunus Armeniaca variety Mandshurica (Maximum) is the formal name of your Bush Apricot. It's from Manchuria and is hardy through USDA zone 6. It's a small, round-crowned tree with reddish bark and sharp thorns.
Bush apricot is not commonly grown, but you should be able to find a source by contacting the California Rare Fruit Growers at their website:
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