I stocked various Centric parts prior to the nondemic. Some of them were backordered for nearly three years. My distributor recently cancelled all Centric backorders as no longer available. If you can find them anywhere, buy them now. I'd rather pay "too much" than not have any.
Dynamic Friction was the last brand of A-body drums I've seen availble, and that was a couple of months ago. I posted the part number in a different "Wanted" thread. RockAuto--who dropships from Centric--hasn't had them listed on the site since July or August.
They are not coming back. By all indications, Centric is no more.
