Unusual Sheaffer Tip-Dip feed

I have a Sheaffer Australia Touchdown Tip-Dip Cadet 23 with an unusual feed. As shown in the pictures, the Tip-Dip hole on this feed (aqua pen) is much smaller than that on the standard Tip-Dip (burgundy pen).
Is this small-hole Tip-Dip feed also found on USA and Canadian Tip-Dips? If so, how common was it?

I must admit I thought that the Cadet Touchdown Tip-Dip Cadet 23 feed replaced the snorkel filler feed. I've only seen Cadet 23 Touchdown tip dip pens with that small hole.