Haven't seen the ambrosia apples but I like Honey Crisp. There are a few websites where you can order ambrosia apples. Looking online for trees, I've read something about the ambrosia apple having protected status in the US and BC.
and here is the history. The Ambrosia apple is an accidental variety according to the story and PG will most likely be hooked once she tries them.
In 1980, when Sally Mennell purchased her orchard it was planted to Red and Golden Delicious, MacIntosh and Spartan apples; Italian Prune Plums; Bartlett and Anjou pears; nectarines and peaches. Between 1980 and 2004 the entire orchard was replanted.
In 1987 a row of Jonagold apples was planted where there had previously been Italian Prune Plums. The nearest apple tree was a Golden Delicious planted among the prunes. A seedling grew up in the row of the new Jonagold apple trees that was different from all the others in the row. In 1989 it bore its first fruit. The fruit was so good and distinctive that the pickers ate the apples before the Mennells could properly taste them.
The following year the same thing happened and as pickers seldom eat apples the Mennells thought that perhaps they should take this seedling seriously. In 1990-91 about 180 trees were budded onto M26 rootstock to see if the variety would remain true to type. It did and by 1993 Wilfrid, Brian and Robert Mennell had propagated about 400 trees. Wilfrid named the new variety Ambrosia because it had the honeyed flavour of "a food of the Gods".
By 1993 other growers had tasted the new variety and were interested in growing it. Wilfrid and Sally were approached by Hugh Dendy, Chairman of the newly formed Okangan Plant Improvement Company (PICO) with an offer to develop and commercialize the new variety. Owned by the British Columbia Fruit Growers Association, PICO was a newly formed company whose mandate was to test, propagate, and develop new varieties in Canada. By July 1, 1993 the Mennells had an interim agreement with PICO to develop the apple cultivar "Ambrosia".
http://www.organicambrosiaapples.com/origins.html