Here is my team size predictions for Canada:
Sports Canada will not compete in: Handball, modern pentathlon. Still possible for no qualifiers in surfing and karate.
Artistic swimming: 8 (confirmed)
Diving: 9 (Could be 8, but I predict 9, 4 men and 5 women)
Swimming: 26-30 (hard to tell, due to the nature of the trials).
Water polo: 12 (confirmed)
Archery 4 (I predict the men's team will qualify)
Athletics: 50 (47 have qualified at the moment, 25 women and 22 men). 50 is a conservative estimate
Badminton: 8 (confirmed, 1 entry in each event)
Basketball: 12 (women's team confirmed)
Boxing: 4 (3 women, qualified, one man is on the ranking list, does not include Mandy Bujold)
Canoeing: 18-19 (4 in slalom and 14-15 in sprint, depending if LVL gets a quota)
Cycling: 21-22 (Road:5, track: 13, mountain biking: 3, 1 in bmx tbc)
Equestrian: 6 (confirmed)
Fencing: 9 (confirmed)
Field hockey: 16 (confirmed)
Football: 18 (confirmed)
Golf: 4 (all but confirmed)
Gymnastics: 6 (5 in artistic + 1 in trampoline, not expecting anymore)
Judo: 6-7 (73kg, 81 kg, 90kg and 100 kg for men and 52, 57 and 63 for women; right now 90kg is out, but if 52kg does well at the worlds, he would be in).
Karate: 0-3 (3 athletes in contention for spots at the final qualifier)
Rowing: 29 (confirmed)
Rugby: 24 (confirmed)
Sailing: 9 (confirmed)
Shooting: 1 (confirmed)
Skateboarding: 0-2 (2 currently in qualification, just barely).
Softball: 15 (confirmed)
Sport climbing: 2 (confirmed)
Surfing: 0-1 (final qualifiers tbc)
Table tennis: 3 (confirmed)
Taekwondo: 1-2 (still awaiting confirmation on reallocation for 49kg)
Tennis: 6 (Raonic. Shapovalov, Auger-Alliasiame, Andrescu, Dabrowski and Fichman), hoping for more, but I think this is it
Triathlon: 3 (1 women, 2 men)
Volleyball: 18 (men's indoor, 2 pairs in women's and 1 in men's for beach)
Weightlifting: 3 (2 women and 1 man)
Wrestling: 4 (confirmed)
At a minimum: 361 qualified, could be as high as 375, either number would be national record in a non-home/boycotted games, not to mention below, which with luck can bring the team size into the 400's!
TBD:
Men's basketball (12 athletes)
Men's baseball (24 athletes)
Men's 3x3 (4 athletes)