If it is at all soothing, I did a very simple mathematic exercise when I lost my Morgaine to a status seizure and came out at roughly 5-6% of greys that were lost to stroke. This was by no means a massively scientific study, I just went by the approximate number of dogs adopted out by my group over a number of years, by how many had seizures. I did this because I knew I was going to get another grey as soon as possible but I needed something to hold on to that told me that I wasn't going to go through the same thing again with my next grey. Of course it isn't proof positive that it won't happen but the 94-95% odds against it did give me a measure of comfort.
My girl had only the one seizure that I was aware of. She was happy and running around and being silly when I left at 8:30 that morning. My walker found her at approximately 2:30 in full seizure. I lost her at 7:00 pm. Needless to say, I know more about how to handle a seizure now but that will only matter if I am there.
Based on the suggestion above, I am going to get BP monitor with an infant cuff.