Family Sterling Silver Pitcher

Sterling Silver pitcher given to me by my grandmother. No known history or if there is, she didn't tell me.

Measurements: about 9 in tall, 3.5 in wide at the largest opening, handle to spout 8.5 in, base length just under 5 in.
Clearly marked on the bottom is:
"R.M" or "W" then a left pointing stag or deer in profile, "&" and an "S" on the top
on the right side "1850"
on the left side "STERLING"
on the bottom "4 PSS", the first "S" looks like it was going to be a "T" but they changed it.

Did some Googling but couldn't find specifics.
I know I can't ask for appraisals but I am going to have it looked at and would love some kind of frame of reference.