Answer: I found only one online source for your Chrysanthemum Leucanthemum vulgare 'Maikonigin'(MAY QUEEN) http://www.arrowheadalpines.com/index.htm
and one source for seeds: B & T Worldwide seeds, and one nursery carrying the plants:
Gilberg Perennial Farm, 2906 Ossenfort Road, Glencoe, Missouri 63038
Hope this information is helpful.
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