Here's a link to a simple cheap way to get a tone alert when you lock or unlock, and set the alarm. You can do this for less than $5 and a little wiring. If you do a search I understand that you can also replace the siren with a different one for around $70. I think that my way is easier, and it is almost free.
https://www.crossfireforum.org/forum...ad.php?t=23009