You don’t specify if you want indoor or outdoor plants. There are several good sources (see links below): Meadowbrook Farm, Primex Garden Center, and Logee's Greenhouse (mail order).
You may also want to contact Otts Exotic Plants, Schwenksville, PA 610-287-7878.
By the way, if you are inquiring about indoor succulents you might be interested in the very active local Philadelphia Cactus and Succulent Society (link below). I've also included a link to our Philadelphia Gardening Guide. Use this guide to learn where to buy plants, what to grow, how to connect with other gardeners and where to learn more about all kinds of gardening. And finally, I included a link to our subject guide called "Succulents." ep
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