"The Sopranos" are holding up HBO for more money.

Just days after the debut of what the pay-cable channel is calling the show's sixth and final season, several cast members are demanding big raises to appear in the final eight episodes, which are slated to air in January and won't be filmed until early summer.

Among the wiseguys looking to fatten their wallets are Michael Imperioli (Christopher), Tony Sirico (Paulie Walnuts) and Steven Van Zandt (Silvio), according to a report in The Wall Street Journal.

The three now are reportedly paid salaries in the low to mid six figures for each episode. Joining the revolt is Steve Schirripa (Bobby Bacala).

James Gandolfini, who stars as mob boss Tony Soprano, very publicly renegotiated his contract about three years ago, reportedly getting a whopping $1 million an episode.

Edie Falco (Tony's wife, Carmela) and Lorraine Bracco (his shrink, Dr. Melfi), are both said to be close to landing new deals, with Falco rumored about to be paid more than $500,000 per episode.

The actors - especially the four seeking to kick-start new contract talks - are using HBO's own schedule as a negotiating tool.

The network plans to air 12 episodes this spring followed by an additional eight beginning next January, but has been careful to portray the entire run as a single season, rather than two separate ones.

The actors disagree.

They say viewers will see the second eight episodes as a separate season - and, therefore, they deserve more money.

"We're confident that everyone will be signed for the last eight episodes," an HBO spokeswoman said yesterday.

Representatives for the actors declined to comment. But "the talks are amicable," a source close to the negotiations told The Post yesterday.

Production on the first 12 episodes is expected to be completed this week, while filming for the final eight is slated to begin in June. But if the talks drag on, the situation could throw a monkey wrench into those plans.

Any one of the actors who chooses to walk from the show could wreak havoc on the series' complicated storyline in what is supposed to be the final chapter of the epic mob saga.

Sunday's premiere episode of the final season ended with a bang - literally - as Gandolfini's increasingly hulking character got shot by his dementia-afflicted Uncle Junior, played by Dominic Chianese.

Although viewers were left wondering how serious Tony's wound was after the climactic scene showed him losing consciousness, it's a safe bet the head of the TV mob family will be breathing for a good many more episodes.