Burried in the text so not easy to find...LiesurePro says the wing is special order from Dive Rite but I saw no mention of it on the Dive Rite site(which doesn't mean it isn't there).
Rec Series | Dive Rite "... Available in single or dual bladder, the Rec Series has 45lbs. ..."
Classic XT Wing | Dive Rite "... Designed solely for double tanks and with the option of a single or dual bladder, the Classic XT provides 60 lbs. ..."
DGX also has them, but shows a full center panel (older? newer?) version for the classic. Not sure which (full or cross) center is current or if one or the other represents NOS.
Both show in stock in the DB config with 16" standard elbow inflator rigs.
Rec series: Dive Rite Rec Wing | Dive Gear Express®
Classic series: Dive Rite Classic Wing | Dive Gear Express®