Promasters use different solenoids from B2K's, and neither of the solenoids used in B2K's will fit in a Promaster without customization. Also, Vikings and Excals use different solenoids than any ICD gun, so the 2-pin solenoid on the AKA website won't work either.
Promasters use the Humphrey HEA10F5-GL-101W. Normally they're available on www.airsoldier.com
, but it looks like they're sold out right now. Do a google search for other Humphrey dealers and make sure you get THAT specific model. Humphrey makes a bunch of different solenoids used in various paintball guns and you have to make sure to get the right model.
The Promaster solenoid is the same one that is used in the Alias Intimidators, so you can try looking for timmy noids as well. If it fits in an Alias it will fit in a Promaster.