its 30 mil in shops. What would be a fair price to sell one of these?

Definitely not 30mil imo. Based on the fact that it was originally 125CSC, I suggest doubling that at least because it is limited and retired. Maybe 10-15? But IDK

i sold it for 5.5 mil

Locking, as this forum is only for items that are not priced anywhere around the site. :)