Need a new main spring for my vintage Lord Marvel

[xzqt]

Hi guys needs some help.

I need a new main spring for my vintage Lord Marvel.
The existing one is broken (crown turn and turn without resistance and continuoue).
Any one can advise which Seiko caliber uses the same main spring/barrel as this ?

Anyone happen to have one that i can purchase ?

Thanks in advance.

[xzqt]

Its been confirmed a broken main spring.

[HiBeat]

Can you give us the case back numbers?

[benchguy]

Of course there is the old-fashioned way.  Pull it out.  Measure the width, strengh and length and make note of type of end...then call the parts houses.  Good luck.