Just an update regarding this post. I have now attached a ladder that appears to be nearly correct, but I am still trying to locate an actual safety devices ladder, as below:
As you can see, this ladder was attached via some kind of welded bracket on the top, which meant it went over the original land rover light guards (would be interesting when it came to change a bulb!!)
Any images of another rack would be greatly appreciated, especially one on someone's current defender (please e-mail these to me)!
Also, does anyone know how the plaque was attached to the roofrack? The rack I have doesn't have any bracket or holes where it would have been attached, so I am presuming that it was simply "stuck" on??