Stop the press! I just dug up more information on Nortzell & Son (instead of sleeping, sometimes I research razors, it's how I keep my youthful appearance).
I dug up a registry of military button makers and found that Nortzell & Son was Nortzell & Broughton until 1832, so this razor is from 1832 at the earliest. There is a large and mysterious gap between 1838 and 1863, but by 1864 the happy Nortzell lot had moved to a different address.
Thomas Nortzell began making buttons in 1809, started making army & navy buttons with the Henry Broughton in 1814 and became a general purpose hardwareman (as well as button-maker) in 1822. It was in 1832 that he kicked Broughton to the curb in preference for his (in this listing) woefully unnamed son.
(and I still haven't done anything to fix it up because I am eyeball deep in deadline for work)