Hello and welcome to the site. It is nice to hear from you, I dare say you will be able to keep your cars running for a few more years. After all how many cars can you drive at once! I guess your annual mileage would be quite low for each car if they were all on the road. Ebay is a good resource of parts but of course glass is bonded in place & not all yards are able to cut glass from its bond or it is not worth it for a small item.
Good luck & keep in touch.
Brian, hello - with such a rare old Espace,I find that cost is worth it, I would not dream of junking the car just because of a broken window, if I had not found a glass then I would have made one from plexiglass that I could curve with a hot air gun and once fitted would look the same. About the only spare we do not have in our stock was the quarter glass. Nice to hear from you.