Bought 951 Non-Resin Soldering Flux. This is the preferred variety. This could be found on this website https://www.kester.com/products/product/951-soldering-flux. 

The amount of Flux that was bought was 1 Gallon (Lasts quite some time). The price was $83.86 with approximate shipping of $43. This was done with a Pcard and a tax exempt form. 

The website used to purchase this was https://www.alliedelec.com/kester-solder-63-0000-0951/70177935/