That first picture is actually a fake. According to the Griswold catalog, these did not come in a box.
I've been looking a long time for a set of No 3 patty irons. Not the box marked 3, but the actual irons marked 3. They are much larger than than the normal No 2 as you can see in the pictures below.
The No 3 set is not common, I've only seen a couple ever offered, and usually more money that I want to spend. This set showed up, not cheap, but close enough for me to buy.
You may see a 5 or 8 cast inside. I don't know if there is any significance.
Tom