The 29-year old is recovering from a shoulder dislocation suffered while playing for New Zealand against England in the Test series in November.
The NRL will allow the Raiders sufficient cap concession so long as it meets the “Josh Hodgson rule” criteria.
It would allow the Green Machine a portion of $350,000 to spent on a winger for next season, but it would mean Rapana must miss the opening 12 rounds of 2019.
He is currently expected to return around round 11-14.
“Our agreement with them is if we’re talking to a player we’ll let them know,” Raiders chief executive Don Furner told Fairfax Media.
“It’s got to be positional, like for like – ‘This guy plays fullback/winger and Rapana plays fullback/winger, is that OK?’ Generally speaking it would.
“We’ve just got to tick tack with them on who it is that we’re talking to and then they would say yes and we’d continue the conversation.”
Furner added that the club has not yet searched the market for a potential Rapana replacement.
“We haven’t put anyone to them [the NRL], but there could be some fallout from other clubs so we’ll see what gets pushed out,” Furner said.
“There’s a few [we have our eyes on], but it would be silly for me to talk names.”
The Canberra CEO also said the club has begun talks with Rapana on a contract extension beyond 2019, when his current deal ends.
“We did have initial conversations with Jordan and then he got injured and went away on a trip, so we’ll get that going after Christmas,” Furner said.
“We’re in no mad rush. I think we’ll sit back and wait and see what happens too, because there could be some movement at other clubs.”