Thanks for the response;Yes,the Drennan quick float adaptor is very similar and does(more or less)the same job.In fact it is probably the successor to the original Swinger(too expensive to manufacture?)but just does not have the excellence in design of the original.It really is hope against hope that the Swinger can still be found but perhaps a Drennan employee can respond??
At the end of the day retaining the float on the line is the whole point and the fish don't know any different whatever I use!!