O'Driscoll was forced off nine minutes into Saturday's final at the RDS, bringing to an end a glittering 15-year career.
Gordon D'Arcy, Noel Reid and Ian Madigan are among a number of options already on the Leinster books capable of playing 13.
But O'Connor admits it won't stop him trying to improve his squad.
"We're looking at options all the time it's important that we get the fit right culturally. It's an important slot - the No 13 jersey has been an iconic jersey for Leinster for a long time," O'Connor told the Irish Independent.
"We need to make sure we get the fit right and as soon as we have got that slotted, if that's an outside body, you'll be the first to know.
"I'd love to bring in five or six but that's never going to happen."
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