Fairly easy to replace those dropouts except for the chrome. Welder probably died.
I have seen those dropouts, but I'm not sure you can buy ones with the same dimensions.
Looks like it's a Longshen LR1 or LR10. Ceeway carries them. Nova used to carry them, but I don't see any now.
Ceeway link: go down to "articulated angle"
https://www.framebuilding.com/NEWPAR...20Dropouts.htm