The non chromed lever on the left is the one that pulls in the clutch. It makes it hard to pedel because when it's pulled in the engine is turning over. To start it just pedel fast and then pull the lever in to engage the engine. The other lever on the left is most likely your front brake and on the right is (at least on my Batavus) the choke and rear brake. You can find the year on a plate stamped on the bottom of the engine. As for the gaskets you should be able to get them from www.mopedjunkyard.com or www.mopedwarehouse.com.
I've never heard of a Batavus Eagle. If you get some pictures of it scanned i'd love to see them.
hope this helps a bit