According to this site:
Magen Shalome, built by Shalome Solomon Umerdekar and his son Gershone
Solomon, Karachi’s last synagogue, was demolished in the 1980s to make
way for a shopping plaza. Most of the Karachi Jews now live in Ramle,
Israel, and built a synagogue they named Magen Shalome. Some Jewish
families do remain, but they prefer to pass themselves off as Parsis
due to the intolerance for Jews in Muslim Pakistan. Their number is
estimated to be around 200 persons.
According to wiki:
The original Ark and podium were stored by a non-Jew in Karachi; a
Torah scroll case was taken by an American Jewess to the US. In 2004
she donated synagogue registers covering the period 1961-1976 to the
Ben-Zvi Institute Library in Jerusalem. Two silver Kiddush glasses
from Magain Shalome were donated to the Museum of the International
Synagogue at John F. Kennedy Airport in New York in honour of the
memory of the late president.