Find files created after a particular time in csh on SunOS

On my SunOS system, I'm trying to find all files created after 7 PM using csh, ls, and awk.

ls -l  "${Source_files_Dir}"/*.zip| awk -v today="$(date "+%b %d")" '{
date=$6" "$7; time=$8; if (date == today && substr(time,1,2) >= 19)
print $9 }'|xargs -n 1 basename

This command works in ksh but not in csh. How can I achieve this in csh? Note: -newermt option is not supported by find on SunOS, so I tried to use the above ls command.