I had the frame on my '78 TripleE break this summer, like yours, while I was on vacation in Newfoundland... Fortunately I was able to track down some "good old boys" to weld it back together with a small plate, that got me home.
NOW, I have to figure out what to do. It "seems" fine, but I feel lucky that nothing more serious happened when it broke. It just drove "funny" kind of wobbly at higher speeds.
Should I have it re-welded by a pro?
What about the other arm? I kind of assume it is ok, since I ended up driving about 10km with the other one broken, which would have resulted in double the stress on the one remaining arm. Is there any sense BOLTING a "safety" plate along the existing frame just in case? (will bolts weaken the frame too much).
Any thoughts from the community here would be most welcome.