lightweight magnetic car door protector strips

[Ci]

Anybody know of effective lightweight magnetic car door protector strips? Which I can pop on the car doors either in a car park or on a car ferry? Ones which won't get pinched and don't cost £50! Someone said they had sourced some from the US. Any experience out there?
Make, rough cost and contact? Google only come up with revolting marrowlike, heavy duty, ugly things. His were vey lightweight, that did the job - protecting against dings.

[Alan W]

This is the only product I have ever seen but not cheap, hopefully the Chinese will replicate and sell really cheap:

http://www.roadstersolutions.com/page1.html