Tudor Submariner Snowflake Franken?

[overgrower]

I took a gamble on the bay with a Tudor Submariner. But unfortunately it seems to have some issues.

1) missing the case reference number between the 12 o’clock lugs
2) serial number 761246 should make this a reference 7021/0
3) It has a quickset date, and from my understanding 7021/0 have an ETA 2484 which is non quickset. It is also non-hacking seconds.

I don't have tools to remove the caseback.

What are your thoughts? Thanks in advance.