Web Services using VB.net + Perl + PHP

Hello , I am trying to migrate a VB.net application to web based framework. The current system calls Perl script/exe on the client machine which open a Command Shell and outputs the program output to the screen as it executes. This provides real time visual feedback to the user about the progress of the application. We want to migrate this application to a web based solution. The web based system needs to have similar behaviour, and I want to know whats the best technology stack to use. I am forced to think PHP as the server side scripting as PHP has API support for Perl so I don't have to rewrite my application that is tested and running fine. Alternatively, I see that VB.net can utilize web services, and if the code can be written in PHP that can call the Perl script on the server is what I want to do. Is it possible to return the output of the perl script to front end and display the output as the code is being executed? Or, Is there a better approach to doing this. Some folks on the internet have suggested node.js but I don't know the intricacies of this new technology stack. Whats the best possible approach to this problem? If we go this approach, the client should be setup as a single page application. We want to use open source solution that interfaces well with perl scripts. Will pay for a working demo.