I bought a sealed dualshock 3 and it's genuine (tested with MGS HD collection) so I figured maybe it can help you as a reference when looking for original ones online :
Official Original Sony Playstation Dual Shock 3 PS3 Controller Multiple Colours | eBay
SONY DualShock 3 CONTROLLER PAD PS3 NEW SEALED GENUINE OFFICIAL PLAYSTATION 711719489658 | eBay
Original PS3 controller Dualshock 3 Wireless Black | Inox Wind
JOYSTICK INALAMBRICO PARA PS3 DUALSHOCK ORIGINAL SONY
Sony Ps3 Controller - Etsy UK
Sixaxis - Wikipedia
Sony Ps3 Controller - Etsy UK
Refurbished Sony DualShock 3 Sixaxis Controller **BLACK** (#) (PS3) (New) on OnBuy
DualShock 3 Repair - iFixit
How to Spot a Fake PS3 Controller Before Opening the Packaging - YouTube
How to Charge a PS3 Controller: 10 Steps (with Pictures) - wikiHow
Official Sony DualShock 3 Controller Satin Silver PS3 : Amazon.co.uk: PC & Video Games
Sony PlayStation DualShock 3 (PS3) (Original) Best Price | Compare deals at PriceSpy UK
Ps3 Controllers -Are these genuine or fake? : r/PS3
With fake DualShock 3 controllers flooding marketplaces, genuine unused ones are getting expensive! I'm glad I have a few in my collection : r/PS3
Sony PlayStation 3 DualShock 3 Wireless Controller PS3 Black Gamepad SIXAXIS UK | eBay
Sony DUALSHOCK3 Wireless Controller - SONY : Flipkart.com
PS3 Controllers,Powerextra Replacement PS3 Wireless Controller,Compatible for PS3/PS3 Pro/PC/Phone/Ipad,Black Playstation 3 Controller : Amazon.co.uk: PC & Video Games
Playstation 3 Controllers For Sale - Buy Official Dual Shock 3
DualShock 3 PS3 controller Black (PS3) : Amazon.co.uk: PC & Video Games
Playstation 3 PS3 Dual Shock 3 Wireless Controller - OFFICIAL,GENUINE & ORIGINAL | eBay
Original PS3 Controller without Blister - DiscoAzul.com
Sony Dualshock 3 Wireless PS3 Controller: Official Sony Gamepad - Blue – Technocontrollers
Sixaxis - Wikipedia
/product/69/9379081/1.jpg?2824 "Sony PS3 Original (official) Controller Pad - DualShock 3 - Black | Jumia Nigeria")