I am a little late to this party, but I just got here.
Here is Mr. Pierce's contact info
rpierce@dom.wustl.edu
He sends you 13 flints, You try one in your rifle, If your rifle likes it you send him a check. If not, send back the flints no questions asked.
They are white Missouri Chert and spark like crazy.
Very good guy to deal with, ya cant beat the price or the service, They are the only flints I use.