I think thats the standard stock on the 50, I've got a near matched pair; .177 and .22 both dated for 1978, and both have pale(ish) stocks with darker staining to the nice deep cut chequering on the pistol grip. They stand out even more with an oiled finish. My .22 had a really icky varnish on it that had started to craze so I sanded it back, sealed and oiled it. Was going quite well until I put it in one of those fleece lined gunslips and it emerged looking somewhat fluffy...