Harrington and all the others buy them in from here
http://www.sgbumperscar.com/index.htm
Buying direct can save you a lot of money. A few years ago Gordon Hunter get together a group buy. I bought 3 sets (1 for me and 2 for someone else) Money paid covered everything delivered to your door. No extras. They were good to deal with. Quality and fit plus the fitting kits are better now than then. Yes the price will be higher now. Mine were about £200 per set cheaper but we did get a quantity discount for over 20 sets, Amazon and 1800.