Need to re construct a 2 hour film

6 months ago I finished a 2 hour long wedding film. The clients were happy with the film but last week asked if I could reedit the first dance part of the film slightly differently - which I’m happy to do. The film was edited on Vegas 10, and fortunately I hadn’t deleted the footage files or project. I had however had a change of HDD and transfer of the files. I loaded the project, and made the reedit, encoded the new version out - and at this point realised that some of the shots earlier in the film have corrupted i.e. have swapped with another clip or a shot I don’t want in there - it looks like the transfer of HDD has thrown out Vegas knowing which event on the timeline belongs to which clip.
So, I don’t want to have to go back through the entire film, checking and replacing clips - it will take days. I don’t have the original rendered out m2v file, as I foolishly overwrote it with this corrupt file (lesson learnt). I do have copies of the original DVD and Bluray discs - can I rip them in Vegas, drop them on the timeline, replace the clip, and render out again without affecting the quality in any way? Or is there another solution out there?

Regards
Martin