Acrylic urethanes are now the standard of the industry. I don't see anything displacing them until waterbase technology either advances, or becomes mandatory.

You should have no problem using readily available products with your basecoat. If you are nervous use the PPG line with it. The urethane reducers are pretty universal between brands. Basecoats, from my experience, can be interchanged, and I have used various brands of clearcoat over them. The secret to the adhesion is more in the process than the brand formulas.