Wow, I think you got lucky too johnnyb.
I have an Airline similar to yours but nowhere near the condition.
The bridge on mine obviously got lost somewhere along the way and someone has replaced it with a Teisco bridge. Yours looks original.
Mine also has the brass pup covers but the brass has tarnished to black.
The electronics setup on mine appears identical to yours. Check the battery holder on yours johnnyb. Mine is stamped No. 173, REYSTONE ELECTRONICS.
And speaking of batteries, I ran across this battery advert for Burgess from a 1952 magazine. Apparently, these batteries are known as "zebra" batteries among those that care about such things.
As for dating the guitar, let me know what you learn from the pot codes. I know these amp in case instruments were made from around 1963 up to 1968 or so. Unfortunately, the Airline version doesn't appear in any of the Wards catalogs I have seen. Given the built in tremolo, I'm thinking our instruments were likely sold in the later 1960's.