You might try
Mancha, although they don't currently list spares for the LCW.
http://www.mancha.demon.co.uk/spares.html
If you need any help, please contact us at – info@designaddict.com
My friend has an Eames wooden lounge chair in which 3 of the rubber shock mounts have separated from the seat bottom and one has broken. I haven't been able to find a source for new mounts. That said, I understand that alignment of the seat is not so simple.
ebay
Not sure which lounge chair you are referring to, but I think either the 670 or the LCW/LCM are available on ebay through Special K Products.
You might try
Mancha, although they don't currently list spares for the LCW.
http://www.mancha.demon.co.uk/spares.html
If you need any help, please contact us at – info@designaddict.com