Yep, the purpose they post beer keg pictures on website is to attract your eyes. However the factory cannot make beer keg if they do not have a certain capacity. To make a beer keg is not a easy thing. First of all the factory must have some molds for beer keg. Besides they must have facilities...
American standard keg should be use D typle valve.
You said you can buy a keg for $40 in China, however it's impossible because the weight of a 1/2keg is 13.6kg, and the ss304 market price per kg in China is 22rmb, thus material costs 299.2rmb= 43.4 usd. Also the "micro matic" brand valve...