A little more inforamtion.
It has suguha (straight temperline) with Ara-nie majiri. The hada (grain structure) is Muji (pearl skin) with ko-itame. The sori is curve at the waist level like Koto style. The boshi is Ko-Maru (small turn around).
The paperwork shows this is not a Tokubetsu hozon, but a Kanteisho Hozon. It is also a bit earlier than 1861. Somewhere between 1848 and 1854.
Here is the origami for your consideration.
Here are some of the pictures of my paperwork.
Overall
Watermarks
Back of paper
Envelope
Close-up of main info (sorry about the color shift)
Seal