There is nothing wrong with your coins as they are serving their purpose of educating.You can't go wrong for £19 for 2 silver coins over 300 years old. Obviously you can google and find many hammered coins to buy.
I have bought from Historic Coinage (Clive), Saltford coins,Gillis,Lloyd Bennet,CC,Vosper and a few others including some US sellers. Auctions should also be on your radar although better pieces are sought after and bargains are difficult.I also often use VCOINS but you need to get in early on new listings.I don't discount ebay on new listings BIN and have sniped a few running their course. Don't forget we have online dealers on the forum who don't pay to appear on the top of google searches. I'm sure other forum members have favourites.Happy hunting.