I had this SS5000 when in around 1980. Bought it in North Point (Chung Kee) for HK$65.
Dry firing it too much and broke it.
Those Ammo were expensive. I remember it was around $5 to $10 per box including case. But some of those are cheap one that I think was made in HK, that the case get damaged so easily. The better one I think was made in Japan (the original make) that never got damage.