Dragon: a single vise on a thread usually doesn't last long and that's why i started the vise repair 101 thread so guys would get their vises on there and we'd talk about them until the vise was repaired or given up and kept as a parts vise. that way if another member has the same questions you are asking they can just check one thread.
i can't tell you how many times I (we've) been asked how to find or make those screw heads or to date a vise, but it's up there with ARE WE THERE YET if you are a parent.
not that we don't want to help you or see you find your answers, but we already have a thread in place that answers a lot of your questions.
on some of my Rock Island vises there is a date stamped on top of the dynamic slide just behind the static. others do have #'s stamped underneath that might be the dates too. post up some pictures of your Rock Island over on the 101 thread and ask questions if you can't find your answers. or just post up the vise pictures and tell us again how YOU MADE the screws because we all have a little different spin on how we make ours. OK?
don't feel left out i start some threads that might have 500,000 views now and it seems like nobody was there for a long time. or when i ask a question sometimes i have to find my own answer if not here on GJ and a member can't see the question by Googling or trial and error.
good luck and your Rock Island sounds like it found a good home.