Hi,
What type of bumper are you looking at building; boxy or tubular?
If you want to build your own, why not design one yourself, at least that way it should be what you want and it will be unique to you, beings you'll be building it (I guess?).
I designed and built my own rear winch bumper with provitions for; a winch, towing bracket, fog lights, quick release mudflaps and recovery points and I was really pleased with it. I also modified my front bumper to house a front winch also.
Steve