The contents of May Morrison’s sweet shop, aka May’s Tuck Shop in the screenplay, Post Office/May Morrison Sweets in the movie.
From what I see in the movie:
In the window:
First we see a chocolate baby sucking it's thumb standing upright on a shelf on the left. To it’s left is a pink elephant. To it’s right are two small pink mice or pigs. To the right of that is perhaps a stylized rooster or maybe a Boobrie bird?. To the right of that are three large-ish balls, one pink, blue and green. To the right of that is an additional pig or mouse like the other two. Hanging above all this is a candy cane shaped like a shepherd's crook.
On the far left border a small, what I would call a king cake which I know from the New Orleans Mardi Gras tradition. A pastry baby. In the middle is a large king cake.
Top row: two pastry heads, some green what appear to be stylized fish heads?, the big king cake, another fish, some chocolate rodents or possums?, some dark chocolate fish
Second row: some chocolate ram’s heads, some pink elephants!, the king cake, more pink elephants, some chocolate turtles
Third row: it appears these are apples or peaches with some sort of wrapping, possibly darkened cabbage. Some sort of candy balls, possibly jaw breakers, area scattered throughout this row. (Gobstoppers?)
Fourth row: chocolate scallops? or fish? and lollipops. On the right there is a chocolate skull! There might be more chocolate skulls beneath that one.
In the store:
All kinds of flotsam and jetsam you might find in a candy shop but also some chocolate skulls, some lollipops, more apples or peaches with the same wrapping beneath them, a chocolate skull next to the pink king cake. A pig after that. On the adjoining counter, hares abound. At rest, running. On the level above the main counter are (from left to right): more of those pastry heads, perhaps a pig’s head after the embossed metal box. (Also a Mexican-style Day of the Dead candy skull with red tips on top) Next to the hares on the adjoining counter (on a Rowntree’s rack): a king cake and a hare and some fish heads above that. Yellow candy apples wrapped in plastic. lady bugs? scattered around - multi-colored circles with spots - could be cookies… Apple blossoms? to the left of the big chocolate hares on the right.
As it’s described in the book:
"An assortment of magnificent chocolate confections met his gaze, as well as curiously lifelike and distended sugar babies. Behind, in glass jars, he could see amazingly large gobstoppers and bull’s-eyes (much more like real bull’s eyes than anything to be seen on the mainland)."
By the front door: a Wills’s Woodbines poster.
In the rack: some little magazines/newspapers including ?, Little Star, Jack and Jill, Fun Time, Sa??? and perhaps a Disney Mickey Mouse cover?
A cardboard full of EMU pencil sharpener near the door and another one above where Howie and May talk. Also SNUFF bags hanging there.
Kiddies Pipes: small plastic multicolored pipes
Lots of Heinz canned products on a shelf…
When Howie returns after seeing preparations in the courtyard we can see:
Lloyd’s Old Holburn Blended Virginia tobacco in yellow tins, seen between May and Myrtle when Howie comes back after the courtyard scene.
To their left, what look like modern Japanese cartoon cat toys stacked in three rows
a big chocolate skull to her right and some smaller candies (frog? pig?)
A RIch Tea poster to their left.
On the right: bags of red chips? “?ree” brand.
Barrat (Everlasting) Toffee Strips? above that?
To the right: Lots of yellow rolls of Sherbert Fountains (candies)
When Howie enters May’s living quarters, we see a painting which looks to be of a ship at sea above the door to the street.
See this blog post that analyzes the items and contemplates re-creating them. Especially note the baby mold!