Get one from NJS Export, they're virtually new..
But in the past ive used a Wippermann 1G8 nice chain but will double the weight of your bike and the normal 1/8" chain tool are not quite man enough to change the length.
in the past to stop things coming undone i have greased them then wrapped cotton thread around and around, put it back on the bike nice and tight.. job done.
...Not quite, signed wheel covers !