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