The only place I recall ever seeing one is in Elite II Frontier. If you have that game (You could probably pick it up second hand for a small amount) go to the galaxy map and zoom right out. Then you'll have to find a way of grabbing the screenshot. Other than that I can't suggest anything you haven't already tried (probably)
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SE4 Code:
L GdY $ Fr- C- Sd T!+ Sf-- Tcp-- A% M>M+ MpD! RV Pw Fq+ Nd- Rp+ G-
/SE4 Code
Work out your code at
http://www.sandman43.fsnet.co.uk/se4main.htm