Wales open their assault on the global tournament against the Springboks in Wellington on September 11, and both players hope to be back in contention.
"It's fine and feels pretty good. The recovery has been a bit slower than I hoped but I'm feeling pretty good. We have a lighter week ahead as we want to build it up slowly," said No8 Jones.
"It's all good, to be honest. It was frustrating not to be involved because of the recurrence of the calf injury," added namesake Stephen.
"But I've had some good news and hopefully will be back running in about seven or eight days."
Wales have lost the last 12 clashes with the Springboks but have thrown away leads in the last two meetings. No8 Jones admits the inability to beat the Bok's has been a major frustration but he hopes that can all change at the World Cup.
"It is a frustration as we have run them pretty close but have not been able to turn them over," added Jones.
"But it's a World Cup and special things happen in World Cups.
"They will go in as favourites, but not huge favourites, so we have everything to play for and it's a massive opener.
"It's such a tough group but we have to thrive on that and try to come away with a win, even if we win all four games 3-0."