Order them, or try some Megs stuff from walmart or auto places. M205, Ultimate line etc..
possibly M205. You would need to do a test spot. I do a test spot on every customer vehicle because some colors and manufacturers are different. Start with the least aggressiveness, then go up if the pad/polish combo isn't cutting it. Some times just changing the pad with the same liquid will help.
Sealant I would say Wolfgang or Menzerna Power lock.
I used a Griots Gen 3 with Lake country white and black pads.
the paint you are referring to is single stage paint or unless the clear coat is gone. You would definitely know that though. With a DA there is little to no chance of burning through the clear unless you are completely ignorant with it.
Before you tackle this, you might need to take it to a reputable detailer. After reading some of your posts.

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