I believe most brand new drums come unlined. They also give you a choice of open or closed top. You'll have more options with the open top drum (includes lid and band clamp).
The factory exterior paint is good and will withstand the temps. Really no reason to strip and use hi-temp paint unless you're looking to change the color.
....UDS....Mini-WSM....Midi-WSM....Mod-ECB....22.5-OTG....34"wood fired pizza oven....