Thanks guys, that all sounds right. As someone who only collects vintage sets and has done so for many years, its pretty rare and exciting to come across a part or even variation that I have never seen before. It's sounds like they made a pretty limited number of the ABS version before switching over, but certainly enough that the part is not truly rare. I went ahead and put in a request to add the variation to the Bricklink catalog, as I think it warrants a separate entry. I agree the ABS shortsword and also cutlass are more prone to snapping, but they are still superior to the soft plastic version from a collector standpoint! The soft plastic variety gets chewed up pretty easily, even just from clipping into a minifig hand, any many of them look bad. By the way, does anyone know the official name for this type of plastic?
With regards to the brown variations of bows/quivers, it is indeed a pain to match them all correctly when refinishing a set. Of course there are at least two different shades of all the brown ABS accessories as well: lances, spears, halberds and all other old brown ABS parts such as the ladder piece and wagon wheels. I just try to keep a good supply of spares on hand!