After yarn shopping, my friend decided on Stitch Nation’s Bamboo Ewe in a shade of gray.
The original sweater is most likely in something like Cascade 220 Super-wash, best we can tell. While 100% wool is springy when knit up, adding the bamboo causes the yarn to relax a little after it’s been washed.
To begin, I knit up two gauge swatches in the sweater’s pattern, on two sizes that I figured already were close to accurate (US 7 & 8). Then I washed them both in cold water & Woolite.
Here are the before and after pictures to show how both swatches relaxed almost an inch after washing.
Either way, it looks like size 8 is the closest to the original sweater, which I had already guessed (always good to be certain before you start).