Thanks for posting.
Circa 1958-59, H&R brought out their newly designed series of "swing-out" cylinder revolvers - the first time they made this configuration. One of this series was the Model 732 - 6 shot, .32 S&W Long with 2 1/2" or 4" barrel. The earliest examples had the full size grip frame with squared butt and either a round barrel or a flat sided barrel. These had a frame mounted firing pin and are considered the 1st Variation, running up to around 1974. The second variation was equipped with a "Transfer bar ignition/safety" system and was also offered in 2 1/2" or 4" barrel lengths. The 2 1/2" version was made with a smaller, rounded grip frame, while the 4"er had the larger, square butt frame. Grip panels colors and materials varied during the 1st Variation from white, to marbled (stag, as it was known to H&R) and finally black.
The swing-out cylinder series (732, 929 and 939) revolvers share a frame in common with the solid frame pull-pin cylinder removal series of guns (632, 622, 632, 922 and derivatives of those), including grip frame shapes and therefore grip panels. Currently, the BB editions (now in the 32 Ed.) printed starting with Ed. 29 are the most accurate, descriptive and comprehensive guides to H&R firearms of all types.
Most of the earlier (as well as several recent) gun guides do not have accurate nor complete descriptions of the H&R Firearms - as not much was published up until 2009 with the publication of the 29th Edition of "THE BLUE BOOK OF GUN VALUES" within which Bill Goforth and I, had the privilege of rewriting the H&R Arms Co. section based upon approx. 12-13 years of research. The forthcoming book, authored by Bill G., on H&R firearms ranging from 1871 to 1986 and beyond, will be the definitive H&R reference guide and the first of its kind.
I've included a couple pics for perusal. Note that the first pic is of a "prototype" R&D example of the Model 732, dating from 1957.