The USA awarded Raytheon a $1.2 Billion package to build the six NASAMs that they previously announced for Ukraine. The Americans announced a total of 8 the air defense systems, and have already delivered 2 of them. According to the article I've attached, the USA will start delivering the systems in the coming months (likely gradually), as they're built. No exact timeline was specified in the article and it's likely to be kept quiet until they are in Ukraine, installed and ready to be used. The total cost includes training, transport, spare parts, technical support and an unspecified number of missiles for the purpose of intercepting Russian missiles.