There is an SMC distributor in Norcross:
Flodraulic Group-Atlanta
1790 Corporate Drive Suite 330
Norcross, GA 30093
Phone: (888) 925-8935
Fax: (770) 925-4207
http://www.flodraulicgroup.com
The part we used is SY3220-5LOU-N7-S; you will also need to buy one fitting for the input side (the outputs already have 1/4" tubing QD fittings), which is part number KQ2H07-M5.
The 5 in the part number is 24V; same part number with a 6 is 12V.
Here is the SMC webpage where you can see the options for this valve series.
Here is the catalog, which you will need to print the sections that show the flow rate and orifice size to the inspectors.
Here is the information you will need to show that they are rated to 125 psi.