I don't know if you can purchase Sony capture separately. However, you can purchase a capture application that is MUCH better than the Sony application:
Thanks for this tip. I know about ScenalyzerLive and I already used this one. Not bad. But for a certain project I would prefer using Sonys Video Capture instead of a "foreign" tool. To be precise, it's not me who needs to use it but somebody who does not own Vegas yet.
If there is a way for him to use Video Capture 5.0 as a standalone version this would be perfect. Maybe even an earlier version would be o.k. but we strongly look for Video Capture instead of any different tool.