This is from the CWGC:
Flight Sergeant (Bomb Aimer)
James P.G. O'Reilly, RCAF R/154098, 429 Sqdn., age unknown, 22/06/1943, Flushing (Vlissingen) Northern Cemetery
Flight Sergeant
William G. Parkinson, RCAF R/105126, 429 Sqdn., age unknown, 22/06/1943, missing
Flight Sergeant (W.Op./Air Gnr.)
Casimir F. Orlinski, RCAF R/134317, 429 Sqdn., age 19, 22/06/1943, Flushing (Vlissingen) Northern Cemetery
Flight Sergeant Sgt
Ernest A. Star, RCAF R/131714, 429 Sqdn., age unknown, 22/06/1943, missing
Flt Sgt
John Kopchuk, RCAF R/132169, 429 Sqdn., age 24, 22/06/1943, Flushing (Vlissingen) Northern Cemetery
Can't confirm Parkinson is buried at Flushing. The Sloedam site doesn't mention him. What's you're source on him?
Regards,
Bart