Simon, One thing I do have, being lucky enough to live reasonably close to Mount Fleet Models, is a fair number of photo's of thier own prototype model that was built by Frank Hinchcliffe. I could put some on here or, as I have done in the past, I can stick them on a CD and post them to you.
I also have a couple of original pictures of her from various sources but they are at home and I won't have access to them for a couple of weeks yet, one in particular is a book about the Ramsey Steamship company which actually contains a colour shot of her alongside in Ramsey.
I also find shots of similar ships of the period to be very usefull and there are actually a lot of them around on the net. These can be usefull in determining typical construction details of the period which may well have been found on the Ben Ain and will greatly assist when it comes time to do the weathering. There are a few shots of other Thomas Brothers vessels and Ramsey Steamship shots at rhiw.com, which are brilliant for getting a feel for ships of this type and of this period.