I see that Shang-Chi's appearances in MOKF 61-75 are listed in numerical order. However, the story in issue 64 is a fill-in during the "China Seas" epic that ran through 61-63, 65-69, including both the prologue and epilogue issues. 65 picks up at the exact moment where 63 ended, so 64 couldn't have taken place between the two. A large part of MOKF 64 is a flashback to "13 years ago" and includes both Shang-Chi and Fu Manchu. I don't know where that would place it among the other pre-SM/E 15 flashbacks, but it needs to be in there somewhere for both characters.
The other main character is a childhood friend of Shang-Chi's named Shoh Teng who dies in this issue. Possibly this was his only appearance. There's also a teacher named Cho Lin in the flashback.
The current part of this story takes place sometime after the "death" of Fu Manchu in MOKF 50, and it takes place in a city with a subway. No other timeline indicators that I noticed. Hard to tell which city it is. There's a street scene on page 3 panel 1 that shows cars on the left side of the road but with steering wheels on the left side of the cars, so who knows? Assuming the city is London, the story could be placed in the gap between 60 and 61, or even before the War-Yore saga, in between 53 and 54. Take your pick.
EDIT: Wait! Let's go back even further. From MOKF 54-69 there were two major story-lines and 3 fill-ins. The major stories were War-Yore in 54, 56-58 and China Seas in 61-63, 65-69. In issue 61, Page 2 panel 3, Shang-Chi thinks about his "last memories" of Leiko Wu, which were the last 2 panels of issue 58. Given that Leiko appears in "The Phoenix Gambit" in 59 and 60, minus the tension that was left between her and Shang-Chi at the end of 58 that still exists at the start of 61, it seems like there might be some other rearranging to be done. The fill-in from 55 could have happened in between 54 and 56, but would make more sense if it didn't.
It's more likely then, that Shang-Chi's timeline should read like this:
MOKF 52
M/TIO 29
MOKF 55 [move to here]
MOKF 59 [move to here]
MOKF 60 [move to here]
MOKF 64 [move to here: option 1]
MOKF 54
MOKF 56
MOKF 57
MOKF 58
T 271
MOKF 64 [move to here: option 2]
MOKF 61
MOKF 62
MOKF 63
MOKF 65