Any idea the quality of weasel fur?
The stoat is type of weasel; its fur is ermine, which sees extensive use on traditional/ceremonial robes and the like. For example, the number of rows of white ermine tails on peers' Robes of State is used to indicate their rank (eg a Baron has two whereas an Earl has three).
It feels very soft but dense. I suspect it would be very warm indeed; I rather like it.