I have a secondhand one in the attic for sale.
1. Rough stiff leather handle, sharp on inside, so that it hurts fingers.
2. Weight of bag without books and dry 2lbs (wet 3lbs).
3. One careful owner 1972-1980
4. Approximately 4000miles
5. There is some banana sadwich debri in inside corners.
6. 3 times tables is scrawled on inside flaps, along with a "Judge Safe Cross Code Badge"
7. Capacity of about 20 books and 4 banana sandwiches.
8. There are also leather back-straps for use when a "donkey" was procured.
The "donkey" was usually a younger bloke who was going home (or maybe not planning to), and you could load him up with 5 or 6 bags, using the straps, and give him a list of the houses that those bags were to be dropped off in.
Funny though.....most of the "donkeys" seem to be driving prestige cars now...................
I can't guarantee it as an extra, but thee is a sacred heart medal sown into the bag, somewhere. It would need x-raying to locate.