Finding a legitimate download for HI-TECH C V9.83 can be challenging since Microchip has moved most of its focus to the XC series. However, it is often still available through the following channels:
Check the "Compiler Archive" section on Microchip’s official website. They maintain old versions for customers with active maintenance agreements or legacy needs. Hi-tech C Compiler For Pic10 12 16 Mcus V9.83 Download
Some university engineering departments maintain mirrors of legacy software for student use. Finding a legitimate download for HI-TECH C V9