Located in Azusa California, Buchanan has or can make wire spokes and nipples for virtually any wheel. They have stainless steel spokes for the Borrani wheels.
This facility, located in Monrovia, California, specializes in the modification of aluminum wheels. Then can make them narrower or wider, depending on your needs. Out-of-round accuracy is less than .005 inches.
A great source for some of the RIV bearing replacements on early Lamborghinis. They even carry the extremely hard to find chain idler double row bearing and the 32 mm double row wheel bearings. A valuable resource for vintage Lamborghini owners.
Located in the U.K. This company restores wire wheels (they have a section devoted to Borrani wire wheels). They also manufacture and sell reproductions that look exactly like the original Borranis (at less money than a Borrani).