Accessible from the top, no tube butting interference, above the bottle braze-ons; I'd go for attempting a fix on that one.
Paint's maybe not going to like it, though.
Although I've never attempted this kind of fix, I'd start with wood blocks on the outside and 1" dowel (don't know if you could find a 1 1/16") with a rounded end on the inside.
But for some correct advice, I'd post this in framebuilders.