You could use the Graph View instead and un-tick the Colour key option in the Colour menu and use option Connect menu>style>show labels

I would quite like to be able to see the key to the side in a bar chart. Is this possible?

Dave

Actually you could remove the existing colour key (Tools>Style>Colour key) and replace it with a new Bar/line view next to it, showing just the Category split and coloured bars.
(Split: category, Measure: f(x)=1, Scale: hidden, Colour: Split)
under Layout menu you can regulate the font size.

Second option would require Stack : category, and labels inside the bars.

something like this...