Also try Taobao (Chinese online store). They sell shoe trees identical to the Woodlores, just not as "cedar" coloured. (Of course, "cedar" trees are not cedar at all. Real cedar shoe trees would probably cost upwards of $1000 per pair. The "cedar" aroma is sprayed on.) Around $15-20 per pair plus shipping.
Woodlore websites says:
Aromatic cedar is made up of white and red sections of wood. The white section is referred to as sapwood. The red wood is called heartwood, as it contains the aromatic oils. Woodlore products include at least 75% heartwood for the greatest aromatic benefit. After one year, a light sanding with a medium sandpaper restores the aromatic properties.
Cedar shoe trees, hangers, blocks and shapes play a vital role in protecting fine shoes and clothing. Aromatic cedar helps to repel moths and other insects. Because we don't coat our cedar with varnishes or lacquers, our all-natural shoe trees absorb moisture from footwear. Aromatic cedar also deodorizes with a forest-fresh scent.