Minty
MINTY
Pale green with white mane and tail, clover
Snuzzle
SNUZZLE
Grey with pink mande and tail, hearts
Cotton Candy
COTTON CANDY
Pink with pink mane and tail, speckles
Flat Foot Ponies
Peachy Feet My Little Pony itself appears to have begun in the summer of 1982. Originating in the USA, the first six little ponies were of one mould and with simple, basic colour schemes.
They also had a distinctive style of hoof not found on any other My Little Pony to follow, nor on any of their own reissues, although there is an existing version of Peachy (peach with pink mane and tail, hearts) sold with Flat Feet,  presumably from one of the earliest Pretty/Grooming Parlour sets :) . 
There is debate about the reissue dates of these ponies. In America they apparently all were released as mail orders in 1986, whilst only Cotton Candy and Blossom were repeat issues in the next year. However in the United Kingdom all six seem to have been sold with both foot styles in stores. Also in the UK, Butterscotch was issued with the Pony Gymkhana
Many thanks to Garej for the use of the Argos catalogue photograph of Butterscotch and the Gymkhana (below)!!

The Gymkhana (1985)

Blossom
BLOSSOM
lavender with lavender mane and tail, white blossoms

Butterscotch
BUTTERSCOTCH
gold with gold mane and tail, butterflies
Bluebelle
BLUEBELLE
blue with lavender mane and tail, stars