These have been in Poundland for a year or two now, for a pound! I've also seen them in sets of three in TK Max in sets of three, and in other brand-graphics in Wilkinson's. That's over eight-inches of wallowing veggie-saur for a pound!
It's also going to lead to the first new polymer tag for years, as it's in this new soft foamed-PVC (plastisols) material which is getting more common with larger toy items, so needs a tag to itself.
Finally . . . ? I don't know for sure? I think they are Marx mini-saur remoulds, as issued by Marksmen a few years ago, but I don't know for sure? At least - I think they are Marksmen's small scale set as advertised, but Kent Sprecher's site credits no small-scales to Marx, so . . . ?