This group is far from common. I have encountered two examples. The first is in People, Passions, Pastimes and Pleasures. Alas, I since learned that the man has a made-up head. The group above is in Staffordshire Figures 1780-1840 and in Holding the Past.
Who made this group? The group has several "Sherratt" features: the brown and white sponging between the man's legs and a dress pattern reminiscent of "Sherratt". However, these are not enough for an attribution. The dress pattern is just a little "off," and "Sherratt" hat plumes typically have three feathers. My gut tells me this is "Sherratt"....but I have nothing that would hold up in court!! The group is a little transitional in styling. Aspects of it are typical of the simpler figure that were made in the Victorian era. On the other hand, it is decorated fully all the way around. I suspect it was made in the late 1830s. The "Sherratt" pot bank was certainly still active at this date, and, indeed, other transitional figures with definite "Sherratt" features are documented.
Last but not least, who might the Royal Couple be? Again, I am not certain. Some have speculated that he is Prince Leopold and she is Princess Charlotte, Charlotte died in child birth in 1817, but both Leopold and Charlotte remained in the hearts of the British public. Leopold arranged the marriage that begat Queen Victoria. In fact, he was the queen's uncle and he was a father-figure and mentor to the young monarch. In 1831, Leopold was chosen as first King of the Belgians, and he married Princess Louise-Marie of Orleans that year. In 1838, they visited England, and perhaps this figure group was made to portray them. Again, I am reminded of how little we know!