The heater was made in July 2007. You’ve got plenty of room to replace the anode, providing you use a flexible replacement, which I sell on the main site. Getting the old one out will be easy as they rapidly lose their rigidity as they’re consumed.
The drain valve is simple. Any 3/4-inch fitting will work, but, using the Water Heater Basics link on the left of the topics index, go there, then to Know-How to see what’s involved. We prefer a ball-valve drain assembly over a spigot type.