It's possible to do this with Auto Hot Key, although there is some mixed opinions about people consider this cheating or not. And this is considered a third party program and banneable, but I have been using this for longer than a year and never got in trouble with it. Eitherway yes it's possible with Auto Hot Key to make a one-button HL macro.
Save the following script in notepad and save it something like hl.ahk and then compile it.
Code:
$+3::
send +3
send {LButton}
+3 means shift + 3 so if you want something else just change it to whatever you see fit.