Over the years I have found random tins (some square with hinges, some
round) are great to use for project boxes. Especially for very small
circuits (ie preamps) that need RF shielding.

Can anyone recommend a good vendor of small tins? Buying them at the
supermarket gets expensive, and I hate wasting mints (I already have
too many! my teeth can't take anymore!). For my current project even a
box half the size of an Altoids box would be too big (I am currently
looking for something the size of a matchbox, or round ones as big
around as a quarter and about 1/3" deep).

Any recommendations would be much appreciated!