HTML Extractor From Document files

We have a C#.net application. We need to extract HTML from word document files for displaying it on a webpage. We have been using word interop file. But it’s not platform independent, we have run into many issues related to deployment of the application on 32 bit and 64 bit platform. I will not be looking at any solutions going this way. I am looking for a 3rd party application to do this job. Now you can suggest me an application (3rd party) or you can write a code and let me test it. If you recommend me 3rd part application it has to be under $150. You have to show me this integrated in .net application and running successfully. I will test it thoroughly. I need HTML extraction for doc,docx,rtf. If you can do PDF if would be great. This html extractor should run on 32 or 64 operating systems such as XP, or windows 7 Thanks