Looking at surname variants, I see there is also a Samuel James Buzza birth reg Dec qtr 1861 Penzance, baptised in early 1862 at Madron to mother Ann(e) Buzza.
Baptism details as follows, from Cornwall OPC:
15 Jan 1862 private baptism - mother Ann, abode Union House
21 Apr 1862 received into the church at Madron - mother Anne, abode Union House
Possible death for him as Samuel James Squire Buzza aged 1, Mar qtr 1863 Penzance.