Cowl from Howl and Cowl Sizing Question

I realized this should be posted here instead. Oops. Original post is below.

I need some help figuring out which size to make. I need at least a 36.5 finished bust but I generally wear a small in sweaters and shirts and a size 6 overall. I think a X-large, which is the only size bust line which will fit will be huge otherwise. What should I do? This is sort of embarrassing, but if you have any experience with making this or just any advice I would aprpeciate it.

I have never made a asweater before and am trying to figure this out.