from your description, I do not think the arrowhead seal you have is correct.
When I rebuilt my car I searched all over the UK without satisfaction.
The common seals LOOK alright but in fact are all just slightly fatter!
The correct, in every detail, seal is only available from Clarke Restorations
in the USA. He does MGA stuff mainly, but has tooled some Magnette items - arrowhead section also correct original shape plated cable/pipe clips.
His address is listed on this web site. I contact him via interweb.

Hello every one,
I have a problem which i need some help on. I have brought some Ramsey spounge door deals and the arrow head seal from woolies. It looks just the same as NTG sell. On comparing the ramsey seal the new one has an open part in the bit that touches the door where as the original seal is flat. the doors are hard to shut but they will do that. Does it get better over time. All so is the arrow head stuck on to the door. My seal has a long side and short side i assumm the long side goes up and the short side is fixed to the door it's self.
Any help would be great.

many thanks

anthony