Chainsaws

I have a four year old 455 Rancher that came with a 20"bar. I'm frequently taking it in my canoe and doing trail clearing work to assist the Forest Service (they have literally no budget at this time). I carry a lot of gear in my 16' canoe and space is a premium. The website specs for the Rancher lists bar sizes as short as 13" but none of the Husky vendors in my area (Spokane) offer a 13" nor can they order one (according to their parts/accessories catalogs).
Is there another model normally associated with a 13" bar that would be interchangeable with my 455?