For a reliable online source I’ve had no problems with Amazon.
Keep in mind though that buying from one of their “partners” is almost the same as eBay so if you want to be sure make sure when you choose an item sold and shipped by Amazon not xyz-partner co. but listed on Amazon.
In my experience if the price is less than the Amazon “with free shipping on order > $25” deal then the chance it’s fake is much greater.
Really, no one buys original quality product from the manufacturer and then sells at a loss online to make money…
