Answer: According to your zip code, you are gardening in zone 6A or the coldest part of zone 6. However, Alstroemeria or Princess Lily is only considered winter hardy to zone 8. Since it would not survive the winter outdoors in your area, I would not really expect nurseries in your area to stock it.
Monrovia is a wholesale only nursery and the plants are sold by independent retailers nation wide. Each store has its own selection of products. Unfortunately I have no way to check which nurseries might have a particular plant in stock, either from Monrovia or another supplier. You would need to check with them directly and ask. There is a zip code based dealer locator at the web site to help with contact information.
If they do not have it locally perhaps they can suggest a substitute. Or, you might find some by mail order. I'm sorry I can't be more specific for you.
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