I've seen complete JD OEM blade kits, including quick attach and hydraulics being sold for less than $800. I think the blade assembly is like $600 new by itself. Based on this, while your homemade blade is nice, I'd think closer to $350 or so. Knowing how nice the power angle is, if it were me I'd be looking to get the real McCoy. I think that pushes the value of yours down some. OTOH, there are guys asking and getting $1200 to $1500 for the complete kits. So, it might be worth $500 to someone. Timing might make all the difference. Not a good time of year where there are a lot of guys chomping at the bit for something to move snow. I'd wait until the first snowfall, and then advertise it.