It'll take too many pieces to accomplish that.
There are 4 in a package. They should work well and the bed be secure and safe. They are not very attractive. But you should be very happy with these sturdy risers. Also, the wide base will help keep the bed secure.
I think so, very sturdy
2 1/2 inch
6 " square
No. I don't have castors either
Need 6, for middle support
The load limit for 4 bed risers is 880 lbs.
Don't think they'd scratch floor. Casters or no casters, would only change the height a little