I remember the Falcon. We sold one for $99.95 in 1973. It was the lowest-priced 10-speed we carried. A bargain and a nice bike to boot. I haven't heard of the Sorrento though. That derailleur looks like a Huret Alvit. Have fun with your Falcon. Be sure to repack all the bearings: hubs, bottom bracket, headset. I've done a cotter pinned crank and frozen bb cups recently, so ask if you need help. Popuki Nui is a great resource on frame restoration.