Hi,
I'm pretty confident that your serial number is "7992
w" rather than No Suffix. A no suffix pistol has nothing stamped under the numeric digits on the frame.
Your "
w" matches the form of one on Joachim's list:
http://lugerforum.com/lugermarkings/...rtz_script.jpg
When you insure this, do it for the retail value of purchasing a replacement from a dealer. Use dealers like FGS Firearms, CheckpointCharlies.com and Simpsons Ltd. for estimates.
1937 was a year of transition. Your all salt blued Luger would have been made toward the end of that year. At the time, Mauser was just getting started with the salt bluing process and their finishes were not consistent. I have a 1939 that is almost glass thin. The finish on yours looks translucent like mine...
The plum color of the extractor is also typical.
Congratulations on your family heirloom. Care for it well. Don't store it in a holster. Keep it oiled and wiped down periodically.
__________________

Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.