You mean a premium nursery with a big selection? On the VA side, try Merrifield Gardens in Fairfax. On the Maryland side, try Behnke's in Beltsville and also Fehr's on 198 and 29. But honestly, Walmart in Laurel MD had a pretty good selection of old classics, if your want a potted rose in a hurry I'd go there. Not sure about Costco. Behnke's for sure has a huge selection, but you'll pay about $25 apiece.

I know this is probably a dead thread now, but google street view for the building was done on May of 2011 - the sabal on the left was fully dead, the one on the right actually had 2 small new green leaves growing. That said the last 2 (and especially this winter of 2014) have been horridly cold, coldest since 1994, and surely any unprotected palm of most any species (except a well placed and established windmill or dwarf) is at best damaged and sabals are probably dead by now :(.

Can't tell ... picture doesn't have enough detail of the bird.

Thanks! here is a better view of the same pic: