DtB317

Hello, I stumbled across this old burglar alarm at Goodwill and had to have it... But once I got it home to play with, it seems it is missing an important piece of its assembly. I Google searched for an hour trying to find the exact model and pertaining information to see if I could order the missing piece OR DIY myself a substitute piece to make this thing functional again, but can't find anything even resembling this model I have. Anybody out there have any ideas? There is no clear brand Or model labeling... Only thing I can find is: "K.H. A241 7904 (OHM) 0.25W Taiwan OC" ^^^ On the back of the speaker/bell of the alarm And "CA328 400B" ^^^ On the circuit board. There is a Google Photos album link at the BOTTOM (edit) of this post, it was the only way I could figure out on how to get the pics to you guys, if there is a more direct and/or preferred method of posting pic, simply let me know and I will be happy to oblige... I know some people can be wary of clicking on outside links just to view images. Thanks in advance! https://photos.app.goo.gl/PNQcXiXcC4Xfz7DA9