Hey Jay,
-Well i "Used" the lens from an A140 projector from the link you show for just messing around and it worked pretty good but the Lenses i actually use in the builds is this:
Thorlabs - LA1213-A N-BK7 Plano-Convex Lens, Ø1/2", f = 50.0 mm, AR Coating: 350-700 nm
^^^Its more practical...