How should I go about this derelict security system? (FBII XL-2)

Our home's security system has never seen use (at least, not intentionally) ever since we bought the house. It appears to be a simple alarm that activates when one of the several sensors around the house get tripped. The control panel is thoroughly destroyed (we should've recorded the passkey from the previous homeowners). Anyways, how should I go about setting this thing up again? We mainly want a detterent for thieves as our neighbors got robbed. Here's some images of the system: https://imgur.com/a/8YiJUd3