I love my hudy stand.
You can put together your own if you can have someone machine a spacer that'll hold the prop out and fit your collet. Then just put a cut for clearence plastic prop on. Use a set of cheap engine mounts and bolt it to a 2x4 that you can clamp to your pit table. Then get a fuel tank.
I haven't seen any other stands that work for car engines.
By the time all that is said and done, you've spent enough where you could have just bought a hudy stand.
Remember you'll need an on road header to turn your muffler away from the prop. I use an old header from an ofna with a weird 90 degree silicone pipe between the pipe and header which turns the muffler away from the prop.
Also keep in mind that while the stand is perfect for breakin, it really deosnt test anything. So testing engines on the stand won't prove much. Its easy to have a good idle when you have a heavy flywheel effect from the prop. So you can prove that an engine runs and makes power, but drivability and idle, not so much.