I might have 2 WD RED 8TB and 2 HGST something 8TB, would need to check. Not sure what prices are common for those nowadays, probably less then what I paid a year ago (or so)
Those have been in an active backup pool though, so not really low hours
Also have some 6TB SAS HGST I could part with (prolly cheaper than the 8GBs), those should be pretty fresh