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Is this possible? Could a Marine chapter symbol be used by others hailing from the same planet/system?

In Helsreach there's a regiment of Imperial Navy fighters that impressed a Marshal enough to be allowed to have the heraldic cross of the Black Templars on their wings.

Sure, Marines often do control their own little empires within the Imperium(see Ultramar)

In which case the symbols would be very similar or the same.

Marine homeworld PDF usually use their chapter heraldry: Ultramar PDF and White Consul shieldworld guard are prime example of this. However Space Wolf Kerls do not wear wolf heraldry IIRC