Actually, the Slavia airguns aren't made by Slavia. They are made by CZ. The Slavia 630 and 631 are just model names. The 631, the better gun with better stock and better trigger, got discontinued in the USA first. The Slavia 630, the lower end gun, has now been discontinued. In this case, discontinued really only means that CZ-USA stopped importing them. The reason that I have heard is that there wasn't enough profit on the guns to justify the expense of importation. That is just a rumor though.
Here's the website for CZ-USA, the importer of CZ guns into the US. As you can see from that site, the only airgun still listed is the Slavia 630 and it is noted as being discontinued. The Slavia 631 was removed from that website quite a while back.
http://www.cz-usa.comHere's the website for CZ, the parent company of CZ-USA, in the Czeck Republic. As you can see on that website, both the Slavia 630 and 631, as well as the more powerful Slavia 634, are listed.
http://www.czub.cz/index.php?lang=enThe Slavia 631 is not the "newer" version of the Slavia 630. It's the "Lux" version whereas the 630 is the "standard" version of the same basic design of gun.
As to the safety mechanism of the Slavia 630, the only safety that is has is the one that blocks the trigger from being pulled. It is automatically pushed to safe when the barrel is opened and cocked. It is a button that is pushed out the rear of the receiver that must be pushed back in before the trigger can be pulled to fire the gun. The Slavia 630 does not lock the barrel in place after it had been cocked and loaded like the Slavia 631 does.
Lawdog,
If you know of a place that still has the Slavia 631s, please let me know. I have the 630 now and would really like a 631. If you know of someone who has one they want to get rid of, I'm interested in buying from an individual also. I can also trade a Techforce 97, and some cash if necessary, for a Slavia 631.