Santa Cruz left Rovers for a big-money move to Manchester City in the summer of 2009.
The Paraguay international is reportedly keen on a return to Ewood Park after failing to make an impact at City.
Allardyce could have money to spend in January following the £23million taker of the club by Indian company Venky’s.
Allardyce told the Daily Mail, when asked if he would like to sign Santa Cruz: “Yes, I think so – there is no doubt about that.
“Whether players of that ilk want to come back to Blackburn Rovers and play for us, that is fine – but it all depends on the financial side of it.
“There will be some finances but whether it will stretch to the size of the sort of wages that Manchester City pay is a difficult one.
“They have blown everyone out of the water recently by the signings they have made and the main reason has been the size of the financial package they have been offering.
“Whether Manchester City can recoup their money or whether we can afford that player’s wages is a difficult scenario to try and get over.”
