Why mess with perfection? The early 80's Floyds came with a nice, brass block - mine is pretty heavy (42mm)! I found large blocks kill the high end and snap of most bolt on guitars. YMMV.
Most Floyd blocks are coated brass. If you think it's steel, you can see if it's magnetic.
Brass blocks are worth a try. They definitely change the tone. Killer Guitar Components makes nice stuff but I've always had to wait awhile for the order to be made.
Is that a top mounted Floyd? It doesn't look like it is recessed but I can't tell for sure. If there is no recess under the route, you want a 37mm block. You can go 37mm L shaped if you like. Either should fit.
There are plenty of guys on eBay who make them for $30ish. Just send them your measurements or buy one that fits. Having a "FU-Tone" stamp on it does not improve the tone.
I have a cs charvel star with a gotoh Floyd rose and I tried the big brass block..
The guitar became woofy and packet the attack that it had...
It made the guitar slower if I could describe it...
At first I did it to thicken up the tone of an emg 81...
After that stock block was back and messes with the pickup height a bit...
Won't mess with this guitar again...
32mm refers to the height not the thickness. They are all the same thickness. The 37mm would have made it so the springs weren't so close to the body but that might be an illusion in the photo.