As Hamm3r has showed u can use @ in the on TEXT, i just thought it worth mentioning that the IF yoy had was incorrect
if ($me isop #channel) && (nick1 isin $nick) || (nick2i isin $nick) || (nick3 isin $nick) { .op #channel $nick }
change to
if ($me isop #channel) && ( (nick1 isin $nick) || (nick2i isin $nick) || (nick3 isin $nick) ) { .op #channel $nick }
reason
The original if would have been true if
(1) ($me isop #channel) AND (nick1 isin $nick) OR
(2) (nick2i isin $nick) OR
(3) (nick3 isin $nick)
you needed to group the OR's into one lot
ON 1:TEXT:$(* $+ $me $+ *):#: { .echo -a $timestamps User $nick has mentioned you in $chan }
if your nick was "|nickname|"
that wont work on _nickname or nickname_ or nickname
it well only work on |nickname| or x|nickname| or |nickname|x or x|nickname|x
ie: if my nick is DaveC you wont get a match if someone says ave