I got a couple items for the collection last year. I saw a picture of a sign like this in the one collectibles book several years ago. I think the book was printed in the 1990's. Never saw a real one untill a guy bought some from an old Sinclair guy and put them on ebay. PASCO stands for the Pan Am Sulpher Company. They owned part of Sinclair in the 1960's if I remember the info right.
This very sign is the one pictured in the Sinclair collectibles book. I saw it in person at Iowa Gas in 2012. A guy brought it and a matching half gallon can to the show to show us but it was not for sale. Last year he found a globe he wanted and he sold the can and the sign to my brother. I traded for the sign and have dibs on the can. Sinclair bought out Cudahy and then used the Opaline brand name.
Also picked up this sign. Probably from the 1930's era and used on the back of a delivery truck. The round ones are a lot more common. I think there is a matching Opaline sign too.
Also picked up a clock at IG
Also picked up a few cans and other things. It was a good year but it is getting expensive to add to the collection.