The stock 974 (Tremont last) is not available at BB. BB's version of the color 8 shortwing bal (M-75 last) is quite different - in design, appearance, and fit - than the 974. I have owned both.
Of all the Alden shell models BB carries, the shortwing bals have probably been the least restocked of them all, at least in the last few years.
$450 is roughly 1/3rd off the current retail price for the 974.