Gilmour is one of 12 capped players on coach Kieran Crowley's 26-man roster.
The four-team tournament, which opens Saturday, also features 'A' teams from Argentina and the U.S. as well as the Uruguay national squad.
Gilmour, who also plays for Alberta's Saint Albert RFC, made his first appearance for Canada against the New Zealand Maori in November 2013, earning his first cap that same month as a second-half replacement against Portugal.
The Canadian roster also includes veteran Ontario Blues back Derek Daypuck, who represented Canada at the 2007 World Cup.
Other capped players include Ray Barkwill, Nick Blevins, Nanyak Dala, Tom Dolezel, Aaron Flagg, Ryan Hamilton, Jamie Mackenzie, Gord McRorie, Patrick Parfrey and Doug Wooldridge.
The tournament runs through Oct. 19 at WestHills Stadium, opening with a doubleheader Saturday featuring the U.S. Selects versus the Argentina Jaguars and Canada 'A' versus Uruguay.
The Uruguayans will be somewhat undermanned for their opening game against Canada since the country's top players will be in Montevideo for the second leg of a World Cup qualifier against Russia. The Russians won the opening game 22-21 in Krasnoyarsk.
Uruguay is ranked 20th in the world, one place ahead of Russia. Canada, which has already qualified for the World Cup, is No. 17.
The winner will join Australia, England, Fiji and Wales in Pool A at the 2015 World Cup.
A Rugby Canada official said Uruguay plans to send seven or eight reinforcements to the ARC after the World Cup qualifier for its second and third matches.
Argentina 'A' won the 2013 ARC tournament, winning all three matches. Canada 'A' (1-2-0) was third behind the American entry (2-1-0).
Canada 'A' Roster
Kyle Baillie, Edmonton Druids, Charlottetown; Ray Barkwill, Castaway Wanderers, Niagara Falls, Ont.; Nick Blevins, James Bay AA, Calgary; Admir Cejvanovic, Burnaby Lake RFC, Vancouver; Andrew Coe, Markham Irish, Markham, Ont,; Nanyak Dala, Castaway Wanderers, Regina; Derek Daypuck, London St. George's, London, Ont.; Tom Dolezel, London St. George's, London, Ont.; Guiseppe Du Toit, UVIC Vikes, Maple Ridge, B.C.; Sean Ferguson, UBC Thunderbirds, Vancouver; Aaron Flagg, Castaway Wanderers, Abbotsford, B.C.; Kyle Gilmour (capt.) Saint Albert RFC, Saint Albert, Alta.; Ryan Hamilton, Capilano RFC, Vancouver; Pete Houlihan, Edmonton Druids, Edmonton; Pat Kay, UVIC Vikes, Duncan, B.C.; Jamie Mackenzie, UVIC Vikes, Oakville, Ont.; Gordon McRorie, Calgary Hornets, Calgary; Dan Moor, Balmy Beach RFC, Toronto; Callum Morrison, UBCOC Ravens, Victoria; Evan Olmstead, Parramatta Two Blues, Calgary; Clay Panga, Castaway Wanderers, Calgary; Patrick Parfrey, Swilers RFC, St. Johns, N.L.; Seb Pearson, London St. George's, London, Ont.; James Smith, Shoalhaven RFC, Calgary; Doug Wooldridge, Castaway Wanderers, Lindsay, Ont.
Head Coach: Kieran Crowley
Assistant Coaches: Chris Silverthorn, Mike Shelley, Graeme Moffatt
Manager: Mark Winokur