A popular supplier of Triumph parts has secured a large supply of NOS keys, some of which are appropriate for E-Types.
I have no financial or other affiliation here - I just know that I enjoy having ‘original’ keys for my British cars and here is an opportunity to pick up one or a full set at (IMO) a very reasonable cost. They have both FP and FS keys - you will, of course, need to know the 3-digit codes.
Here are the details:
http://trf.zeni.net/wc/featurekeys/index.php?menu=&page=3
FYI - Albert Runyan and his father Charles are great Brit car enthusiasts who have done much to support TR owners for many decades.
To link directly to what is available:
FP626 - 709: http://trf.zeni.net/wc/featurekeys/index.php?menu=&page=4
FP711 - 750: http://trf.zeni.net/wc/featurekeys/5.php
FS876 - 907: http://trf.zeni.net/wc/featurekeys/index.php?menu=&page=6
FS908 - 955: http://trf.zeni.net/wc/featurekeys/7.php