Hello markyoung11 from Glenwood Springs, Co. Gee, I know where that is. You're in the mountains for sure.
Welcome to Air Forums and all things Airstream. Looks like you are headed down that slippery slope with your 67 Overlander. Renovating these old Airstreams is a fun hobby, and eventually they get done.
Replacement glass for the mid sixties windows is available from Vintage Trailer Supply. You better bookmark their website, as they are a great source of old Airstream parts.
I've been working on my 66 Trade Wind for two years. I'm installing a new and very expensive RV fridge. That's a pretty major project too. After the fridge, I'll install my new stove and call the thing "travel ready". It is going to Colorado the first of August.