I've got an optics project that requires half-silvered mirrors - so light can pass both ways. In optics lingo this kind or mirror is commonly called "beamsplitter".

Can anyone recommend a supplier for this material? It could be 1/8 or 1/4, but I'd prefer 1/8". I won't be buying huge quantities right away, but a minimum purchase is probably not a problem. A California-based supplier would be a bonus.