Here's a pretty cool collector's item from the Canon rangefinder era: A collapsible 5cm f/2 Serenar lens in Leica screw mount, with caps and matching hood/filter set.
Both the lens and the hood are quite rare, having been in production only from 1947 to 1949. The hood is, if anything, even harder to find than the lens; even more so complete with its leather case and unmounted filter set.
The lens is in superb optical condition (just a few cleaning marks) and perfect mechanical condition, having returned from a CLA at DAG Camera in May of this year. There are some light scratches on the collapsible barrel (none through the chrome), and some minor usage marks. The diaphragm blades are clean, but show some wear. The rear cap has the correct "Made In Occupied Japan" engraving, and the front cap is a chrome "Canon" push-on cap (to be honest, I don't know if it's a 1940s original, or possibly a 1950s replacement). Interestingly, this early Canon lens has a non-click-stop aperture scale going from f/2 to f/11, and it turns in the opposite direction (Nikon-wise) from later Canon lenses (which go Leica-wise).
The hood is also in excellent condition, with a bit of dulling to the chrome finish, but no dings or dents. There are four unmounted glass filters (yellow, orange, red and blue) in superb condition. The filters event have the remnants of their original cellophane wrappers and two leatherette disks to protect the top and bottom from getting scratched in the case. (The case has only one minor flaw: one of the small leather straps that hold the stack of filters in place has pulled loose from its rivet.) The hood consists of three parts: a 40mm screw-in adapter ring; a screw-in filter retaining ring; and a push-on shade that fits over the filter retaining ring.
Given the rarity of this complete set and its condition, I'm asking $695 plus insured shipping.
For references, I'm active and have good feedback on Rangefinder Forum (same username) and my eBay ID is dogleg31.