That's a shame. Yes, I would have been interested as I don't have an example of one of the rarer Elizabeth II florins (1954, 1957/58/59). I would say £25 is conservative; scarce UNC 50s florins and halfcrowns were massively hyped in the late 60s, but florins continued to circulate until 1992 so the scarce UNC dates are indeed rarer than the equivalent halfcrowns, and now their values are AT LEAST 50% higher than the halfcrowns. The main reason for the rarity is that no-one collected the early years of CuNi as there was no silver content, unlike Geo VI which were put aside in large quantities, especially after the metal change was announced postwar; this is why 1944-46 are so common in BU.
If you've got similar 1950s florins, let me know the dates and I might be interested!