Forging and metal working is easier with an anvil...this dude shows you how to make one cheaply...some welding required.
that's not a bad idea even if you have an anvil - never seen that long of a RR tie plate however - but there could be an old deal machinery base plate that could serve as a welding & bending jig also .... I've picked up several RR rail anvils over the years - handy to have them bench mounted for those small fab jobs ....
Anvils can be made from all kinds of heavy scrap metal, I have a wide variety of anvils that are home-spun, and they work as well as the ones you get in a store. In Eastern Europe and Asia and Africa, there are video of men working sitting on the ground, pounding out a knife on a homemade improvised anvil. Grant you the bigger anvils are better in some ways, depending on the size of the material your working, but if the forge can achieve enough heat necessary, a small anvil and hammer and patience can accomplish a lot.