Before you proceed any further please check out this blog post i created on installing and downloading of Nokia and Lumia phones Firmwares Here.
Most of the download links are not in english, you can use a browser with authomatic translation i recommend google chrome browser.
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 630 RM-978 And Lumia 640 RM-1073 with product codes by commenting on this post.
Model: lumia 630
Model:Microsoft Lumia 640 Single SIM LTE