Sorry that I can't be too much help, but from a picture in one of my repair manuals, I believe that your Mabie Todd is an eyedropper filler-specifically a #8. Hard to tell from your photo and my lack of knowledge.
Sorry, but I have nothing to offer on the others. I was going to suggest going to the Washington DC Pen Show in 2 weeks but then I noticed your location. Guess that's out of the question. LOL.
There are still at least two pen shows left in the UK this year if you're willing to do a little traveling. Probably more fountain pen knowledge in one place there than you will find anyplace else.