My english bulldog chews mine through a couple times a year. Best Buy and Walmart charge outrageous prices for chargers ($75-120). I normally find non-OEM chargers on eBay for $10-25 that are identical to the OEM ones that come with your laptop. Hope this helps!
You might alsotry here also. http://www.priorityelectronics.com/product/HP/#PavilionI have ordered several for my ex-girlfriend/good friendand her 15 y/o son who both have Dell laptops. The wires pulled loose on the first two we got, but they are both kinda rough on these things; using them in bed and on the floor, leaning against the wall to charge, etc.
They come with a one year warranty, so I had no problems exchanging them. Not top of the line...but you get what you pay for.