I heard sometime last year that a mint roll(s) of CHP1841 had been found, the finder sold them with multiple listings on Ebay, price started top end but flooded the market, in the end they were selling in bulk for less than half book price. There are several now in slabs both this side and the other side of the pond, all very high grades, similar happened with CF1825 a few years ago, too many too soon for the market to absorb and keep price buoyant.
There are CHP forgeries, dates I have seen are 1825 and 1826 modern looking contemporary copies, 1845, 1848, 1851 and 1860 there is an error with all, an exaggerated long serif to the first 1 of the date, and the identical flat worn reverse used for all.