Microsoft released a newer version: version from June 2016, which is part of the June 2016 Update Rollup.
Windows Update Client for Windows 7 and Windows Server 2008 R2: June 2016
This update contains some improvements to Windows Update Client in Windows 7 Service Pack 1 (SP1). This includes the following:
An optimization that addresses long scan time for updates that's reported on some computers.
Download:
32Bit:
https://www.microsoft.com/en-us/download/details.aspx?id=52976
64Bit:
https://www.microsoft.com/en-us/download/details.aspx?id=52974
Stop again Windows Update service.
Try the downloaded update and see if it speeds up the installation of Updates.