Before you proceed any further please check out this blog post i created on installing and downloading of Nokia and Lumia phones Firmwares Here.
Downloading and Flashing a Firmware can help you to reset and recover your phone software at anywhere and anytime without a need for an internet connection.This can really help you if your phone is not responding, frozen, experiencing software related or software update problems.
You can also request for more Lumia 640 firmwares with product codes by commenting on this post.
Model: Lumia 640 the Dual Sim the LTE (4G)
Product-RM: the RM-1075
PWBASSY DS LIGHT SWAP ENGINE GLOBAL 059X0X8: RM-1075
DS GLOBAL SWAP 059X1N2: RM-1075
VAR APAC 1A CV 059X1R6: RM-1075
VAR IMEA LK CV 059X1S9: RM-1075
VAR IMEA ZA CV 059X1T7: RM- 1075 VAR, EURO 6A CV
059X167:RM-1075 VAR IMEA the IN CV
059X185:RM-1075 VAR, EURO the FR CV
059X2B8:RM-1075 VAR the LTA 7R CV
059X2S3:RM-1075 VAR, EURO 3V CV
059X269:RM-1075 VAR APAC PH GLOBE SL
Software Version: 02166.00000.15103.05001