Here it is, anyway.
And here's Mary in her early 40s.
There are several rather good portraits of Keats- including a life mask and a death mask- but then Keats- though only a middle-class vulgarian- had friends who were artists.
Here's one I hadn't seen before- a charming silhouette by Marianne Hunt.
There are, of course, lots and lots of portraits of Byron. Most of them serve the legend. Here's one (by Count d'Orsay) that subverts it, showing him as nervy, querulous and (unmistakeably) balding.