I use a good grower's mix too, like ProMix or Fafard, and sometimes add pine fines or vermiculite... it depends on what I'm trying to germinate.
Rick, you should be able to find vermiculite at any hydroponic store. Or on Amazon, it's only $6 for 8 quarts. Just how cheap are you???
https://www.amazon.com/dp/B00LY9O6F6/
Karen
And in your area, can't you just blink and have an Amazon delivery in a nanosecond?