Sounds like a Dino sign, made from 1959 on. Two different sizes. I would guess $1200 and up. Saw a very nice small version at Iowa Gas this year, think they were asking $4K for it. It sold, probably came down a little. Some people can get more money for the same item in my opinion. They are known in the hobby and have a reputation for selling nice original stuff.
$3885? Crazy high for that sign in that condition. A lot of people look at the hobby as an income and have way out of line prices. Look at auction results, a lot of stuff sells for prices at auctions that most probably would not sell if priced at the final hammer price at a show.
What the others said, its a Sinclair can. I have a quart oil can that is similar. Don't have a grease can like that. More interest probably to a Sinclair collector than a general can collector due to the plain look to it.