mblue Make an account and go to T83 as algent said.
https://support.brother.com/g/b/downloadlist.aspx?c=as_ot&lang=en&prod=dcpt300_all&os=128 ---give them this link. it looks like brother has .deb and .rpm packages at that link.
this is an all-in-one with a scanner so they offer the scanner driver seperate but it looks you will need both components
also--did any solus repo brother packages work for you? try that first.
also--in typical brother fashion they call your computer DCP-T300 DCP-T500W DCP-T700W on the manual cover. I always interpret that as semi(?)-interchangeable? If one of those drivers exist then...maybe?
edit: fixed link