Sniper's "jacket", I've found, is most similar to a shooting vest.
The example here gives the basic shape, minus the high collar, and colors, but the wrong color scheme. --> http://www.gandermountain.com/modper...D=GSHOP_420791
I would recommend having your own vest custom made to save on expenses and to have it fit you perfectly.
As for the Huntsman, it's a hardwood recurve bow (the TF2 wiki says), which you could buy from anywhere between $200 and $800. Or you could make one yourself to give it that extreme curve. Not sure on what materials to use, though. Asking around to other Snipers that have the Huntsman already would get you some fast answers.