Hi there and nice to see you here.
I have built a 1:76 scale model of 'Presto' and there are some photos on this site. Don has also built one but in a larger scale and his photos are listed here too and, I think, a movie of her. There is also a Russian member who has built something similar and again photos/movies are posted here.
I am interested in the subject of your research in general terms but don't have any major research of my own to reciprocate.
I originally found Paddleducks whilst looking for information on paddlers in the Austrian and Italian navies at Lissa, 1866. At least one of the Austrian avisos was Glasgow built. I wonder if you have any information in this area??
Cheers....Bernie