The 222 is a Featherweight with a freearm - imagine a freearm in the 1940s! Singer is reported to apparently have decided American women would never buy it so they never sold them in the US. They are much higher in price because they are more rare. There was a limited number of them made.
The 221 comes in the usual black that were sold in the US and are still popular. There are also tan and white/lt mint green that were made in Scotland and/or Canada/England. Again more limited in number made so cost a bit more. ALL of the Featherweights still run like champs.