Actually, I found very few higher resolution sources... From the cards featured above only Gandalf is made from an high-res art. All other cards are actually made from the original cards and A LOT of "remastering" in Photoshop...
German cards are the best source material available for this, then japanese cards, then spanish cards, and only then english cards. All other printed editions are way too grainy to fit this purpose...
While high-res art makes things REALLY more eye-candy, their quality may vary a lot.
You also have to keep in mind that once printed at "regular" size (63 mm x 89 mm) most details will be indistinguishable:
- metd_wolfriders.jpg (1.09 MiB) Viewed 6694 times