Never buy a pan from the dealer. Always post a wanted thread and likely you'll find the pan you need for super cheap money. yeah..even I have a spare on the shelf. However if someone is changing the gasket on it. They can put it on the floor and tap it back out with a block of wood. If it were actually dented badly.
The gasket on these sucks a little. It's not an impossible job, but it's a pain in the neck. (This is why I went aluminum pan, it's much easier to do if you ever need to reseal it.) Another thing that many people don't notice is ....does the leak appear to start seeping from the trans side of the engine. If it does, then likely it's leaking from the rear engine cover gasket. This gasket is behind the flex plate and quite common. I've seen more rear cover gaskets leak/seep than rear main seals.
On my Regal, it was an oily mess when I got it. I did the aluminum pan (engine sealant is it's gasket) and cleaned everything up. Soon after I was leaving a single drop in the garage most days. I smiled and turned the radio up to keep it from being an issue (drown out all problems with louder radio, it's the pro way to fix stuff). When I changed my transmission, I drained the coolant and oil also and changed the rear engine cover gasket and the rear main seal. The main seal is in the rear cover. Sure it wasn't any fun and it took longer to swap the trans. I also tried to remove the oil pan to reseal it, because...it seriously looked like the pan seal was leaking. I er uh..used too much sealant when I did it originally. Was smacking the pan with a rubber mallet, block of wood..you name it.. darn thing wouldn't budge. I put the bolts back in and hoped for the best. These days my engine/trans are 100% dry.
On my former Bonne..I chased an oil pan gasket 5 different times. Each time it kept leaking. When I cammed the car, I did the rear engine cover gasket. Never another seep, drip or thought of a leak.
Likely you do need a pan gasket, but don't assume that doing it would fix all your leaks.
Damn rear cover gasket is torqued to something like 2ft lbs.