"In reality there's always going to be a gap between what is offered here and elsewhere, but it's a case of whether the gap is too large."
Sharrock said that should not be taken as a suggestion that the NZRU had "low-balled" the 48-test veteran, saying Kaino was comfortable where he was in the pecking order.
With the attrition on his body that comes from his role as an enforcer, Kaino would be foolish not to consider setting himself up financially as he is clearly nearer the end of his career than the start.
An overseas stint now could leave open the possibility of a return to New Zealand rugby before the next World Cup, though those plans are always fraught - see McAlister, Luke, for Exhibit A.
Kaino had surgery this week to repair his damaged left shoulder. The bruising blindside flanker partially dislocated the shoulder in the second-round loss to the Chiefs, but played on.
The injury did not settle after the match and scans revealed a piece of bone had been chipped off the joint.
Sharrock said the injury had been "a bit of a handbrake" on contract negotiations as interested clubs and Kaino himself wanted to see the prognosis for a quick recovery before committing to anything.
Rehabilitation on the shoulder is expected to take six months.
American Samoan-born Kaino has formed one of the great back-row partnerships with Richie McCaw and Kieran Read. His early career was pockmarked by inconsistency, but in the past two years he has rarely put a foot wrong.
He was the All Blacks' best player in their successful World Cup campaign, playing all but 90 seconds of the tournament.
He narrowly missed out to France captain Thierry Dusautoir as the IRB's player of the year.
"As a result of the World Cup he's become one of the, if not the, most sought-after players in the world," Sharrock said.
In recent times three players have worn the No 6 jersey for the All Blacks, and Adam Thomson, Victor Vito and Liam Messam will be in the frontline of thoughts about a test replacement.
McCaw might be another option. He has played his 103 tests on the openside, but there have been times at Super rugby and provincial level where he has switched to other loose forward roles.
He could move to blindside in his comeback with the Crusaders to allow a possible international combination with No 8 Read and opensider Matt Todd to advance even further. If the selectors decided on a positional switch for McCaw, then Luke Braid would probably challenge Todd for international promotion.