BBM's website is now announcing a new set commemorating the 30th anniversary of the Seibu corporation acquiring the Lions. It's a pack-based set (as opposed to a box set) with cards for both current and former Lions players. The website shows a Kazuo Matsui autographed insert card. I don't know if that means that he or other former Lions now playing in the US (like Daisuke Matsuzaka) are in the set or not. I've always been a sucker for these sets (sometimes more sucker than I'd like), so I'll have to see if I can at least get a couple packs, if not the entire set.
I think this clears up the mystery (well, for me anyway) of the Lions box set I mentioned a few months back. When I originally looked at the babel-fish translation, I'd noticed it said something about the "Hakata Lions". What I didn't know then was that Hakata was a ward in Fukuoka where (I expect but can't confirm) Heiwadai Stadium used to be. Heiwadai Stadium was the home of the Lions before Seibu bought them and moved them to their current home ("the Seibu Dump") in Tokorozawa. So this box set commemorates it being 30 years since they moved. (OK, so maybe I'm displaying a keen grasp of the obvious, but I'm happy I figured it out, even if it took me a couple months...)
Here's a card showing Heiwada Stadium from the 1992 BBM set. After the Lions left, the stadium didn't have a permament resident until the Hawks moved from Osaka to Fukuoka after the 1988 season (when Daiei bought them from Nankai). It was home to the Hawks until the Fukuoka Dome opened in 1993. I'm not sure if it's still standing or not.
Update: I forgot to mention a couple things. The first is that the set should be out in late May, according to the web site. The other thing is that this is actually the second BBM set that commemorates Seibu buying the Lions. The first was a box set that came out in 1999 to celebrate the 20th Anniversary.