Just arrived at this city for chinese studies after four years of absence. According to Wizards of the Coast there should be a game center located near the North Gate of the Sichuan University Wangjian campus called “SGM Board Game”, but according to the neighbouring places the place has moved, but I can’t find it.
There are definitely a lot of Magic players in Chengdu – you can buy booster cards in every 7-11 in the city. Most of the people playing are using Chinese cards, but there are pockets of foreigners in the city playing this. Perhaps someone will emerge or send you a PM, but I know that as recently as a year ago there were people organizing Magic games through this forum.