Most common Lionel prewar items you find in Europe I think are 1688's and 1689's, sometimes only the engine and sometimes a set or what's left of it: either the passenger litho cars or the freight cars, a baby Ruth, tanker and a caboose. I wonder if Lionel ever seriously gave it a try to set foot on the European market. Or didn't they need it as the US market must have been big enough? I can imagine that US trains were less attractive for Europeans, at the other hand, they were toys. As a kid I didn't bother if a train or car was French, British or German, as long as they fitted on the tracks. And common practise was (and still is) bringing for instance German engines in a British livery, for export reasons.
Lately I saw on an Ebay site (Ebay.nl, that's Dutch) a Lionel steamer. It was a German type BR50. Strange to me, but the seller seems convinced. There was a box with it too. I never heard that Lionel made any foreign engines. This one looked like a rather recent production.
regards, Kieffer