Stacey is Barbie's British chum. She came along during the MOD era. Stacey had a new face with a tiny smile and rose cheeks. She had rooted hair in blonde or titian and hair styles varied. Early Twist'n Turn and Talking had almost the same hair style but the part was on different sides and the talkers had bangs, while the T'nT had a tiny curl in front. Later T'nT Stacey dolls had a short flip cut.  
Stacey has two different year stamps inside the neck rim, 1965 and 1968. I am not sure what the difference is. 

Stacey
Copyright: 1965/1968

Photo courtesy of Dagmar Krutoff

#1125 Talking Stacey, 1968
head is on a Twist'n Turn body

In the early 70's, Barbie and her friends hit the beach. Sun Set Malibu was the long going name of the beach series and Barbie got a new face. This is one of my childhood dolls and one of the reasons I started collecting face as a sort of grown-up adult ;) I think the let-loose life of beach bums need Barbie to be more "happy" so she borrowed the face of Stacey for many years to come. A tanned version with painted teeth and the almost turquoise Barbie blues. Very blonde hair, rooted with a side part, long, straight and shiny. Malibu Barbie varied a lot in looks as she was made in different plants. The Japan versions all are Stacey but there has been later SuperStar versions from other plants. 

The Sun Set - Malibu Barbie 1971 - circa 76

#8587 Standard Barbie, 1974
European release
Looking the same as Malibu, but with a light (often yellowed) complexion, honeycolored hair and pink standard body.

#2166 Barbie, 1977
European release, also called Speil mit Barbie in Germany
These dolls suffers from hardened plastic and the heads shrinks. Body is a tanned Malibu with PTR arms
 

Not even Stacey got home free from copy cats. I found this Hong Kong made, hollow, cheap plastic clone doll and just had to have her. She doesn't have hair, but come with a wig (or several, since I have seen more styles) in a long red flip style.

noname Hong Kong clone