Karen,
Not sure if they will be portraying the Seven Stars Artillery. I know this year that the infantry with me (19th Louisiana)will be portraying Miles Louisian Legion and there are some great guys from the 9th Texas that will be portraying the 165th NY Zouaves.
The Port Hudson event is usually held the last weekend of March every year. I haven't heard of them taping the event, but you might want to check with the park for that. I do know that when they fire that 30 pounder cannon, the ground shakes. You can contact the park at http://www.crt.state.la.us/parks/ipthudson.aspx It truly is a fine place to visit. A few years back, I worked on a project with Doug Owsley of the Smithsonian Institution on excavating the graves of the local cemetery to determine if the people buried there were soldiers, slaves, civilians, etc. We found one that appeared to house both a Union and Confederate soldier which they ended up reinterring together. LOTS of trails there to wander as well. I do hope you can make it one day.