It cost that much due to the screen, IIRC. Laptops in general were prohibitively expensive (I have a 486 lappy from the same era that went for nearly 3 grand new - cost me 120 quid a year ago).
Buying the screen singly was a lot more than it would have cost to buy a couple of hundred, as laptop manufacturers are wont to do. It was also quite big - if you think of the size of an A1200, the screen filled the lid of the laptop vertically, and as I recall it did the full 640x512, not the more common 640x480.
Anyhow, this screen had to have a special interface built in-house, and I believe that a certain portion of the cost was labour and headscratching compensation.
I'd love to come across one again, just to see if it ws as cool as I remember...