There are some wonderful examples of extant sleeve 'ruffles' or 'flounces' at http://www.larsdatter.com/18c/engageantes.html and there is a Mill Farm Pattern.
We see them in portraits from the mid-18th Century, and whilst mostly worn by the upper classes, there are images of them worn around the home. In the portrait below we see the shift showing under the outer sleeve ruffles of a laundress, though this one looks a little too genteel to my eyes.
|“Laundress” by Henry Robert Morland|
I found this image showing an elaborate sleeve ruffle - three outer ruffles joined by two inner silk organza ruffles.
|Joseph Blackburn, 1762|
Today I pinned my sleeve flounces into the sleeve to get an idea what they looked like. I have made mine from an extremely sheer light cream silk cotton fabric that goes well with both my colouring and with the cream silk of the gown. I'm hoping that when I add the outer silk flounces that they will support these inner flounces a bit more. Next time I'd like to try using a stiffer silk organza.
If you want a pair of engageants just like this I am happy to take orders in my Etsy store. I have plenty of this silk cotton fabric in either white or ivory (pictured).