This is a genuine BMW trunk lid lock with micro switch, part number 51 24 8 169 532. The number stamped on the part is 51248169532; BMW's catalog files it under the short number 8169532. You will find it on our Interior Body shelf, under Other Body equipment parts.
It fits every E36 body style (318i, 318ti, 320i, 323i, 325i and 328i, 1992–1999), with the M40, M42, M43, M44, M50 or M52 engines — and the European-market versions.
BMW draws it on 6 diagrams, among them Hood parts, doors/locking system (03_3840) and Hood parts, doors/locking system (03_3841). It weighs about 175 g (0.4 lb).
We have not had one on the shelf yet. Request it and we will tell you when one comes off a car.