Had a look at internet pinball dB and the photos there are pretty inconclusive but do look like the thin wood screw style. I am sure someone here with the game will provide a part number. Push comes to shove you can drill bigger holes if you want to use your original posts

I have new posts which are a metal thread the same as the other ones on the game. Maybe there were originally woodscrews but changed over to metal ones somewhere during its life.
I didn't think of looking on ipdb, good idea though, thanks. I have the original flyer but I couldn't tell there either.