I eventually managed to find terrors of the tomb, dark forest and artifacts and allies on boardgamegeeks with some Belgium sellers. Prices varied from 7-12 Euros. Once seller had all 3 with about 18 Euros for postage and packaging. Another seller had two of them but would send them in small parcels so was only looking at a few Euros delivery. Delivery was actually really quick. All in English and in new condition so I was really happy to finally complete the sets I'd been missing.