Who has the pattern or the link for a bolero pattern that is basically a knitted rectangle, then folded in half, etc etc?

It might be here…

Well, you don’t really need a pattern since it’s just a rectangle, folded in half and sewn up part way. It’s based on your measurements, from one wrist (or elbow or wherever) to another, and as wide as you want across your back. Usually 12-18" is a good width.