The usual stock looking, direct bolt-on, small bore Master that I like to use is the Raybestos 36406 15/16 NEW .
https://www.rockauto.com/en/moreinfo.php?pk=309117&cc=1088760
Dr Diff offers a new style plastic master even smaller in size, same small bore, with an adaptor plate, requires some plumbing that a lotta guys like, shown in this thread.
inding link.
Good luck