The SBDC101 looks like a dead ringer for the SBDC051/053/055 with a different dial. If the movement is the same 6R15 then I'd expect MSRP to be 100,000 JPY. I guess this fills the gap for anyone who thought the SLA017 was too small or too expensive, or wanted an 051/053/055 with stick hands.
I'm still a little confused.
And, I'm with icnbne above, the 55th anniversary is a bizarre milestone. We're now in Omega Speedy Pro anniversary territory with these.