May work..no way to tell til you try it. I haven't ever used a "tripod". I have bipods that mount to the stock of a rifle and shooting sticks that I carry that I prefer for sitting, standing or kneeling for shooting. The bipods work best off a bench.
Good shooting sticks cost $35-40. Bipods can be had for somewhere between $35 and $100 depending on model and brand. I have a friend who build his bench rifle rest out of a car scissors jack and a soft front bag full of sand. Cost him $20.

Find a piece of closed cell foam rubber and gorilla glue it to the top.

There is always a chance of ricochet bullets when you shoot steel. I made a target much like you described and never had a problem but I kept the bullets on the paper and avoided shooting the steel. Also depends on the style of bullets and chambering of the gun. 22 long rifles are notorious for ricochets and any hardball ammo is bad too. Hollow points and varmint bullets rarely ricochet by design.