Farrar has been hired, in part, to fill the void left by versatile back William Hopoate and veteran winger Michael Robertson, while hardworking backrower Shane Rodney has also moved on.
One desired outcome from the Sharks trial would be to find instant replacements for Manly's departed players, with Toovey admitting it would be difficult in the short-term to overcome their loss.
"It's hard to replace the experience of guys like Robertson and Rodney, but it's also hard to replace William Hopoate who always found a way to the tryline,'' Toovey told AAP on Monday.
"We won probably two matches specifically on the back of him finding the tryline when others would not have got there.''
Manly's regulars will likely only get a 20-minute spell as they continue their preparation for England.
"The majority of the grand final squad won't be playing very much football, but they'll probably get 20 minutes,'' Toovey said.
"It's very much a hit-out for us and about trying to get our timing right on a few things.''
Co-captain King (pectoral muscle injury) is still seeking medical advice on his possible return date and appears unlikely to play.
The same goes for David Williams, who injured his neck against Melbourne last year but has made a full recovery, Tony Williams (quad) and Galuvao (Achilles).
All are still under consideration for the WCC match, but Toovey insists he won't take anyone overseas who will be underdone.
"It's very difficult because obviously you've got to take a small squad over,'' Toovey said.
"We'd like to think that squad will be fit to play because it's hard to travel that far and go over there and not have any backups.''
- AAP
