wow... I just called my local dealer in San Diego,CA Toyota red/orange coolant $21/gal!! This is concentrated. A bit steep.
After researching around though...Peak and Prestone extended life versions of their coolant advertise them as phosphate free and silicate free. Also, they certify them as compatible with many makes of cars, including Toyota and Honda. Check out their websites and search around with "phosphate free". It's alternative that may be worth considering. I know their will always be people true to the Toyota parts, but I'm just pointing some info out that maybe useful.