I tried to find one that would let me cradle and run a 235 engine. Wound up buying some 2" square tubing, steel casters and fabricating my own. Have about $75. bucks in materials in it. Have a pic in my "Tips and Tricks Webshot album.
I just retrieved my rebuilt 235 yesterday and although I had to make a couple "adjustments" it provides me with a sturdy platform with great access. If anyone is interested, I can provide the dimensions.
Dave