As the Gothic Crowns were not produced for circulation, most of the specimens were very well preserved. In fact, it is not difficult to find Gothic Crowns in public auctions all around the world graded by NGC or PGCS as PF63 (their hammer price is around 6.000 euros). The facts that most of the specimens are graded by grading companies, and that they can be found on auctions all around the world show how internationally demanded these coins are. However, the coin in the auction is not as good specimen as PF63. Taking into account the hammer price of some coins graded lower than PF60, such as this coin (1600 GBP) and this coin ($3500), I would consider that 2800 – 3500 euros is a reasonable hammer price interval.
Description from the seller
Europäische Münzen und Medaillen, Großbritannien / Vereinigtes Königreich / UK / United Kingdom. 1 Crown 1847, Silber. Gothic Type. SEA-3883. NGC PF-58
Schätzpreis / Estimate: EUR 3200-3800