Answer: Thank you for asking. The Lantana requires full sun to bloom well; I might also mention it is not a hardy plant in your area so would not be expected to survive winters outdoors; it can however be grown as a container plant and brought indoors for winter if you wish to keep it from year to year. The aster would also be better in all day sun and a spot with good air circulation but it would tolerate a half day of shade. Filtered shade probably is not bright enough for it to bloom heavily but you could always experiment and see if you like the results.
You should be able to find both empty and preplanted hanging baskets at your local area nurseries or even at the "big box" stores along with other decorative containers/spring planting supplies. Indoor plants for hanging baskets would typically include Pothos, Spider plant, English Ivy and Grape Ivy. For a really bright southern window you might try Burro's Tail (a succulent) or possibly Bougainvillea both of which can handle hot sun. Your good houseplant nursery should be able to show a selection of plants.
Monrovia plants are sold nation wide. Unfortunately, I have no way of checking which nurseries or garden centers would have specific plants or supplies in stock on hand or be able to obtain them for you. They are independent stores and each carries its own selection, so you need to check with them directly and see. There is a dealer locator at the web site that is searchable by zip code and provides contact information.
If they do not have it, perhaps they can suggest a substitute. I'm sorry I can't be more specific for you and I do hope you find what you are looking for. Best of luck with your search!
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