The trade gives the Redblacks some depth under centre after Jeremiah Masoli was injured in a 28-13 loss to Saskatchewan on Friday.
“We’re pleased to be able to add Nick to our locker room at this point of the season,” Redblacks general manager Shawn Burke said in a release.
“He’s an experienced player in our league and we look forward to having him on our side as a member of the RNation family.”
Arbuckle completed 74 of 115 passes for 892 yards over five games with the Elks this season. He threw two touchdown passes and was intercepted eight times.
The 28-year-old native of Oxnard, Calif., has played in 48 career regular-season CFL games with Calgary, Toronto and Edmonton. He won a Grey Cup with the Stampeders in 2018.
Masoli, meanwhile, will need surgery to repair a bone-related leg injury, a team spokesman said. He’s expected to miss 10 to 12 weeks.
The Elks, who are last in the West Division standings at 1-4, return to action Thursday in Montreal.
The 0-4 Redblacks, who share the East basement with Hamilton, will visit the Tiger-Cats on Saturday.