I should have looked closer at the photos of the Silent 700/1200 I just bought. There's a very clear auction photo that shows DIP switch 4 does switch between "300 baud" and "1200 baud". Maybe it's the same for Marc's 1200 bps model 703.
Silent 700/1200 auction (ended): https://i.ebayimg.com/images/g/lQ8AAOSwnLtglDa7/s-l1600.jpg Auction photo of 700/1200 DIP switch legend and CMD key options: https://i.ebayimg.com/images/g/lQ8AAOSwnLtglDa7/s-l1600.jpg
