I don't think so, Franck. The size of the brooches might fit, but a pair of mismatched earrings doesn't seem very likely around 1835. Here's a larger photo of the engraving by John Cochran.



And here is a photo of Henry Collen's portrait of Victoria, Duchess of Kent from 1829. Cochran's engraving is based on this painting, which is in the Royal Collection.