Although it is very hard to find #67 rubber bands on the NET I have found a place called QUICKTECH HOBBY (rubber bands & hobby supplies) that probably have every size bands you would ever need, including 3 different package sizes of #67 relatively cheap. I do believe I will be ordering from them. Will check them out in more detail when I have the time.
Here they are . . .
http://www.quicktechhobby.com/Mercha...Code=APASIGRUB