Help locating a mainspring 29C UT

[EdB]

Hello Everyone!

Looking for assistance in locating a Seiko mainspring or a mainspring that would work with the 29C UT movement. From my understanding the movement is part of the 66B / 6620B family. I have a Seiko #401660 but have not been able to locate this spring by this number anywhere I've looked. I did do the manual calculations for the mainspring required which are as follows:

Length 351.50  mm

Height 1.33 mm

Thickness .09 mm

Any help would be appreciated. 

Ed... 

 

[WatchMaker]

Cousins lists Générale Ressorts item 3510 which ties up with this ebay seller too: https://www.ebay.com/itm/-1X-1-mainspring-3510-1-35-X-11-9-Muelle-380-1-30-X-0-85-seiko-66A/274501708367