Need help with identifying the age on this kettle/ restoration tips

Hello everyone I recently picked this up for 10 bucks on marketplace and I’m having a hard time figuring out what year this is from, I have started getting the thicker dirt/ grime out of it, I do have plans to change vents and grates if possible, it does appear like the leg posts are starting to rust from the inside so I am a little concerned about that but I’m not sure how much of an issue that will pose. Any guess on the age or tips on trying to restore this would be greatly appreciated.