So I'm over at the library, pawing the maps and atlases of the U.K. and Ireland and such. I found a map you might like in The Reader's Digest Complete Atlas of the British Islands. Dig the complete title from the title page:
Dang. Even the shrimpy little Channel Islands get billing over Ireland. That's some stone cold partisanship right there. Anyway, dig this little inset map I found on page 83.
That map is extra crazy if you don't know that old maps are (literally) oriented with east up top instead of north. Of course, for your campaign you could ignore that fact and place Ceylon at the North Pole.
I think my favorite feature of this map is that the Tigris and Euphrates don't seem to empty into anything in particular.