Ellpea, as far as I know, none of those machines have the ability to chain stitch.
I think there is a German made 400 series that can be adapted for chainstitch, and many of the "newer" singers (I think the 600 or 700 series) were convertable. There are a lot of Kenmores from the 60's/70's era that are also convertable.
I've seen advertisements for an adapter for the Wheeler Wilson, I think it's for the older style with the "weird" bobbin holder thing, not the style the 9W has.
The older Standard Rotary machines also are convertible, and probably the most affordable/available. Both the "stout" and the earlier "slim" models are convertible, but they take different adapters (called Spiders because of their shape).
And there is always the Wilcox Gibbs, or National/Eldredge Automatic (a WG copy) but they are chain-stitch only machines.