Proofhouse.com has sn tables for Winchester.
Winchester had a lever shot gun with this mdl number, is that the gun you mean?
Return spring is sprung
Best left to a gunsmith
Search on youtube for Winchester 1300 assembly, they are internally the same.
Yes, but ejector spring may need modification- slight change in slot for spring.
Best left to a trained gunsmith.
A number of rifles did not have serial numbers prior to 1968. but, that has changed.
Remove the 2 screws from the end or the mag tube and the cap and spring will come out. Do so carefully as the spring is compressed
That is correct if the spring is upside down it will not lock back. The big end of the spring goes toward the cap.
when did spring make 12g single barrel shotgun serial number 30368
You need to take it to a competent gunmsith
You need a good gunsmith.