No more DL JFK/BUD, much to our chagrin.
Sure, fly AF to CDG and buy cheap zed (zed low). Probably on Hop! I've been several times when we covered it. It was one of Boss' fave routes. Our second fave just below PRG. When are you going there? Happy to offer any advice. I think you'll find more if you search BUD here.
You can likely zed from any major EU city. Check matrix.itasoftware for options, then check $ on DLnet.