This is a genuine BMW gasket stoplamp, part number 63 25 8 360 221. The number stamped on the part is 63258360221; BMW's catalog files it under the short number 8360221. You will find it on our Lighting shelf, under Flash signalling light (authorities). It supersedes the older number 8357526, so a part carrying that number is the same part.
It fits the E36 sedan, coupe and convertible (318i, 320i, 323i, 325i, 328i and M3, 1992–1999), with the M40, M42, M43, M44, M50 or M52 and other engines — and the European-market versions.
BMW draws it on the Third stoplamp (63_0276) diagram. It weighs about 11 g (under 0.1 lb).
We have not had one on the shelf yet. Request it and we will tell you when one comes off a car.