Anyone that has looked for an anvil recently, can tell you they are expensive. Creative people are the ones looking for them. Therefore, if you can't afford one right now, get creative. A section of railroad track, is a good (inexpensive) start. You could do what this person did , and add to it.
Stacking saw ponies cut on a ShopBot. A single sheet of 3/4" plywood makes four complete ponies that stack/lock together. Details and files posted at http://www.talkshopbot.com/forum/showthread.php?t=13360
Tip: A simple T-shape support, made from scrap plywood or MDF, mounts in your portable clamping workstation, where shown. Once you have matched the support to your table height, drill the base of the support and insert dowels to instantly set the height each time. To make this table even more versatile, use it with your bandsaw and miter-saw, drilling separate dowel holes for each height.