I use an REI backpacker's poncho.  It's longer in the back (enough to drag on the ground, so it folds up with snaps so you can use it without a pack).  Inexpensive, tough, and big enough to cover pack and me to  (I think) mid-calf.  Not blaze orange, though, and I don't recall if that was an option.  Some reflective tape might work, but a blaze orange "blob" would certainly stand out!

Retired medical technologist and engineer
REI member since 1978
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