I'd get a used one. Keep an eye on the classifieds for something that is under $50. You want it to be good enough to take an edge and not have a lot of problems like frowns, chips in the edge. Stay away from old sheffields/wedge grinds. It can be a shortened blade too since those tend to come cheaper. It'll hone just the same. You can try eBay but you might not know what you're getting and it could be a boat load of trouble. I used to have a stash of such razors that I used to practice on. Once I got myself up and running, I handed them over to someone else to use for the same purpose. Keep an eye out for something cheap but something that won't make you pull your hair out trying to figure out.