If you can't find a handyman to repair it you might consider placing a permanent splint along it - thin strip of steel of a couple of bits of strip timber one each side - screwed on .
Alternatively you might make a replacement part and fit it to replace the original but it would mean re-wiring the hub for all the other ribs too.
Good luck...
Peccavi, July 2009
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I can answer this question...
Any place in the DE County area , to fix a broken rib in new patio umbrella?