i can always count on you sirThey are needed to do the pressure test not the flow test and it's possible to rig up hoses and gauges to do the same thing. The flow test only requires a graduated cylinder or beaker to catch the gas and some way to turn the pump on. Be careful that you don't burn your garage down.
A guick look for the 09940-40211 shows that it's available from many sources, but it's not cheap.