I totally get the Master ID. It LOOKS Master to me too. I want it to be Master. However, some have said the lavender points away from Master.
Curious marble.
On a technicality even if it's Asian, it's hard for me to see it as "Imperial" because to me it looks truly vintage and since the Imperial Toy Co. was founded in 1969 and didn't initially import Asian marbles, if we have truly vintage marble here, it couldn't have come via Imperial. But again, that's just a technicality since we use "Imperial" for a wide range of Asian marbles, not just the ones distributed by that particular company.