The W&W 8 was made until 1880...and yours would have been made between Sept 1878 and the ending date, whatever that was of 1880.
I'm excited for you! I love mine, even tho I don't use it because it still has some of the bed decals and I'm scared of ruining them, it does have a really nice stitch! I will, eventually, make SOMETHING with the machine...
I see a metal "hemmer" insert, do you have the glass foot? Did you get any of the glass inserts? It's great that you have the spooler (bobbin winder)!! Those are most often missing!
CONGRATS!!!