Plaster and Paint Over Panelling
I would think your best option would be to remove the paneling first. Especially if its the ukky stuff from the 60-s-70's. Now if its nice paneling, you might want to save it, strip it and use it another day....
So with the paneling removed...you can buy the synthetic plaster mixture at either the hardware store or one of the HomeDepot/Lowes bigger home centers. You can apply it over the wall....let it dry and paint it. There are many different rollers out there that if you ask the local hardware guy about matching the texture, he can advise what to use (low nap, high nap, patterns, etc.)
Being its one wall, its pretty easy for you to get it done in a day...
Hope this helps