almost worth it for the brakes (rare) cranks (really rare in tandem form) and hubs (same). As to the frame... it could be a decent bike or it could be a dog. Its a tossup with french bikes from the 80s.
French threading could be an issue . . .
With twin laterals, IF they have small re-inforcing bars/bridging between the twin laterals it should be good; without the re-inforcing bars could be a bit whippy with a couple of hard stompers.
Price is great, parts are old, but nice. TA cranks are/were great, huge choice of chainrings from 22 to 60T!
Owned a 1975 Follis (similar) and it's a good introductory 2-seater.
If it fits physically, and your budget, go for it!