In North America specifically, all steel is primarily recycled. I believe there are no longer any steel mills left that alloy steel from iron ore, all process scrap metal from industry and post-consumer reclaimed, and have for several decades.
Pricing raw sheet metal usage is quite easy but laborious. Use your awesome CAD skills to estimate how much steel, aluminum, etc. your parts will use, either raw weight or square area. Phone any metal supplier in your area and they should be able to enter your minimal data and give you a price. Be aware though that for volume production this is a misleading figure as the cost of raw material is a small contributor to final part and finished product price. For a one-off prototype, design or statement piece, it’s a valid exercise to estimate your cash outlay.
So here’s my interesting anecdote. Doing the exact same as you on a project… I got a price for a quantity of .250" aluminum plate of $111. Two days later when we realized that one prototype wasn’t enough (surprise!), the same material was quoted at $540! Some metals market maker in New York, Chicago, London, Rotterdam or Singapore had made a move on aluminum futures and that’s the result.