If you are contemplating a flashlight, go with a DKG (they are still around) mount for a maglite which can be converted to led…some probably are but I haven’t looked. You have an 80s bike and these came out in 80s…here is one I have on my 86 Rodriguez tandem…I had the matching but no longer available seat post mount too but some a$$#ole stole my wife’s Brooks pro, Suntour XC seatpost and the light when parked at our Paso hotel following Eroica a few years back. Still chaps my hide…they stole our Scott cantilevers too.