Use this one with your vise grips for $25..
Shop Superior Tool Pex Pocket Crimper at Lowes.com
I kinda like this one,
Shop Kobalt PEX Crimp Tool Kit at Lowes.com
for $59 and that's the cheapest I've seen a full sized crimp tool..
Cheap, but more that twice the price of the pocket model..
I just need one for 1/2" for small projects, where it makes no difference if it takes an extra minute or two to crimp each fitting..
I do like the small one, since it can be used it tight spaces..