imported post
Dixie Gunworks is probably the "go-to" source for antique and reproduction firearms in the US.
Here is their current list of ready-to-fire flintlock pistols:
http://www.dixiegunworks.com/default.php?cPath=22_92_187_188
And if you want to save a few bucks and build it custom, they have kits as well:
http://www.dixiegunworks.com/default.php?cPath=22_162_195
Blunderbusses are relatively difficult to find. Genuine antiques are rare, and expensive when they do come up, and to my knowledge, nobody currently makes a modern reproduction Flintlock Blunderbuss. If you REALLY want one, you're probably going to have to find a smith who can custom cut the barrel for such a project...
There were a few European smiths making them in the 1970's in Belgium and Italy, but most of the independent historical smiths in Europe have been driven out of business by their crazy firearms laws...
There IS a VERY pretty one on Gunbroker.com right now, though.
http://www.gunbroker.com/Auction/ViewItem.aspx?Item=169062117
French, all-steel, and beautifully made. It's a .75cal bore, and the seller claims it's fully functional, except that the flash hole isn't drilled (which they will do for US purchasers). It's not cheap, but the price is certainly reasonable considering the craftsmanship, and the rarity of this type of gun in a modern, functional piece...