I wanted to keep a stock front wheel, partly because that way I could compare head-to-head. I bought a wheel from a crashed 2001 from a local guy for $55 and removed the spokes and rims.
New rims seem to run from $125 to $200. It's not clear if you can get one for the stock hub, or it has to be drilled custom. I've heard of Excel and Sun being used in 2.5" width.
Spokes range from $30 to $70, don't know what the difference is.
Places like East Coast Wheels or Woodys charge $50-70 for lacing and truing.
I found a local (MA) shop, Custom Wheels, that will order the parts and build it for me if I tell them what I want. But they specialize in custom Harley wheels so they can't advise on the choices.
Add it all up and you're looking at $300+ and the price of a new tire and tube.