I worked for Exide for 20+ years. This is a great battery for starting diesel engines. We sold 1000's every year from our branch every year.
The one thing that I'll add is to look at the date stickers on the side of the battery.
There will be a small, 1/2" or so, that will have the month and year that it was manufactured. The branch had a year from then to sell it as new.
There is also a "shipped to" sticker, about 2"by 2", probably on the other side. It will have the month and date that it was shipped to the customer.
But, even if it's a little over those parameters, $60 for a group 31 is a fantastic deal!