There's one on "regular" ebay if you search for "marauder oil gauge" or it's just here:
http://www.ebay.com/itm/Oil-Temperat...#ht_1287wt_698
$40 with about $12 shipping. I'm not really sure how that compares to the euro site. It seems like the german one was a little cheaper for the item (as it looks like it's on clearance) but the shipping seemed higher? I'm not sure. YMMV as they say. (your mileage may vary) literally