For your unit, yes this error relates to the "Drum Unit".
The most affordable one I could find and also has free shipping is below:
Lastly, for the steps to install it on the unit, you would need to follow the step by step guide below to do so properly:
1 Remove the TD cartridge (Toner Cartridge). Hold the drum cartridge handle and
gently pull the cartridge out. Dispose of the old drum cartridge in accordance with local regulations.
3 Remove the new drum cartridge from the protective bag and remove the protective cover from the cartridge. Then gently install the new drum cartridge.
When closing the covers, be sure to close the front cover securely and then close the side cover. If the covers are closed in the wrong order, the covers may be damaged. Do not remove the protective cover on the drum portion (black paper) of
a new drum cartridge before use. The cover protects the drum against external light.
Do not touch the surface of the drum (green portion) of the cartridge. Doing so may cause smudges on the copies.
4 Gently install the TD cartridge. Close the front cover and then the side cover by pressing the round projections near the side cover open button. The drum
replacement required indicator will go out and the start indicator will light up.
Glad I could be of assistance and god bless!