Sapphire crystal, Argon filling - when were they introduced for the Sinn 103?

I wonder from which year (I think in the mid nineties) were sapphire crystal and dehumidifying capsule/Argon filling available for the Sinn 103 St?
I've seen recently some 103 St Sa models without the capsule/screw at 8 and they are quite appealing for me (most of them in bad condition though).
So I think sapphire was a few years earlier available. If anyone has more precise info I'd be happy with that.
Little help: I've bought my first new Sinn back between 1996 and 1998 and it was a 203 Ti Ar, so from that time Ar was surely available.
Replies in German are also highly welcome. Thanks in advance,
best:
Robert