I think those rice-paper sherbert sweets were called U.F.O.s, Alison.
As you say, Fizz Bombs came a little later and were the fore-runner of "Space-Dust". Made by the same company (Somportex), Space Dust came on the scene in the seventies and was a massive hit here.
I was at this time a budding, young entrepenuer (think Rodney, in fools and horses). My business partner (Del Boy) and I noticed how Somportex seemed to be launching their new "Space Dust" product on a regional basis and, being up in the North-East, we knew they would take a while to get to us, so we went and hired a truck, drove South and bought up all the wholesalers stock.
By the time Somportex got to our neck of the woods we had shipped many truckloads into the shops and the craze was all but over.If I never saw another packet of Space Dust it would be too soon!

For the benefit of our American friends I should explain that "Del-boy" and "Rodney" were two characters in a British comedy show called "Only Fools And Horses". A show about a hapless entrepenuer/con-man and his dim-witted brother.

The mention of Midget Gems and Dolly Mixtures, reminds me of the high shelves in the sweet shops, where the rows of glass jars lived.
Cough-Candy-Twist(meant to be medicinal?) and Apple Tarts (Soooo tart my face crumples at the thought) I can taste them now!

My business partner and I, spurred by our success with "Space Dust", decided to open a pick-and-mix sweet shop and use the new-found wholesale contacts to supply us with stock.
Given that most of our previous business dealings involved job-lots of seconds (imperfect stock) or bankrupt clearances bought at stock auctions, it was something of a surprise to our friends that we were "going legitimate".
One such friend visited the shop on our first day of trading, to wish us luck. Helping himself to a wrapped mint humbug from the display, "Well at least these can't be seconds!"
As he unwrapped the humbug he noticed that the stripes were only on the wrapper!
The shame of it!