hah... that's hilarious... a bunch of canadians telling somebody who lives in pennsylvania where to get plants in canada. this is great guys... maybe we can get somebody from the states with some more appropriate answers?
i know first rays sometimes carries some things and he's in doylestown. i do know that his business is an on-line one run from his home and i think he has a family too. i'm not so confident he'd enjoy visitors coming to check out the goods so to say.
now home depot and lowes definitely carry some things as well as ole wally world but i am skeptical that they'd stay appropriately sized personally. i do know that walmart has several color broms at this very moment but i've heard that thay force them to flower early and the pups have the potential to get even bigger than the parent plant you purchase. the ones they have right now are already tank buster size for my 50 gal and are wide enough to lean on the front and back glass at the same time already. last year on mothers day i got my mom an orchid too from one of them guys but the damn thing was almost 3' tall already.
now something of a vine, fern, etc. that would creep and fill in an area i have no issues with since it could always be trimmed back but being stuck with a brom that already spans more than the depth of my tank from front to back and has the potential to produce pups that will be even larger is not my idea of filling a tank unless i only want 2, maybe 3 plants in the whole tank.
now, what you could do is check here and see if anything catches your fancy on the various sites listed... good places to buy... please add to it!
by the way, i live in lower bucks county right by the burlington, bristol bridge. there's lots of nurseries, garden shops, a couple michaels, a.c. moore's, hydro shops and walmarts, lowes and home depots out the wazoo, even a kmart but i've yet to find appropriate epiphytes for a viv in any of them. i have found plenty of desert plants and succulents as well as some vine plants that would be nice size (some would need trimming from time to time and i have yet to check toxicity on all of them) but that's about it.
rubiks, where do you live? approximate area is fine.
i do know that the flower show or something similar is coming back to phila area soon. i think some time in april. one just passed 2 weekends ago too that we apparently missed. i was too busy and broke thanks to the berks reptile expo though. that, from what i hear should have plenty of smaller exotic plants for sale.