It's not that easy, then again t's not terribly difficlut, but it's more
than getting it down in numbers and then parts, you need to etch out the
circuit boards and you must have a template or the least a simple
circuit board to mimic, maybe you should buy One Unit and make the rest
yourself and hope it comes out cheaper.

about ten years ago I made a ac/dc power supply circuit to supply for a
nice portable tv an uncle had given me, the original had cracked and I
just fancied a new oe after repeated jumper and glue tricks, so I got a
PCB Kit from Circuit Masters & etched it out in my mini backyard shop,
the iodine solution stunk a bit, but I was lucky I only had to mimic
some fairly simple tracks and transfer all the components to it, you
will need to get all the components the mfgr uses on that model ( they
may or may not be exclusive or available) if you don't find a more
feasible model in a good Electronics Circuit Cook Book.

good luck, if you're into your security system you'll enjoy it