Don't know if you have figured out how to toast the rice for tea yet but I just came across your posting as I was looking for the same thing. Following is a recipe for a hot toasted rice cereal that you can just follow to toast the rice. I will give you the whole recipe as this is the way I found it online and it is a wonderful breakfast to have on a cold morning with your green tea.
Good Luck and Enjoy
Homemade Brown Rice Hot Cereal
Really delicious used in various bread recipes. Also can use basmati, jasmine or regular white rice, but brown is the healthiest.
4 cups short-grain brown rice or long grain brown rice
1/4 teaspoon salt (optional)
In clean, dry skillet (preferably cast iron) toast brown rice on medium heat. Lower heat if rice starts to smoke.
Toast rice for about 10 minutes, stirring constantly so that grains do not burn. Rice should turn a medium brown. Set aside to cool slightly.
In blender fitted with steel blade, or in grain mill or food processor grind browned rice to the consistency of medium coarse cornmeal (grainy but not powdered.).
The grinding process will have to be done in 3/4 cup portions to allow the rice grains to grind effectively.
To store: Place ground rice cereal in airtight container or "ziploc" bag. The cereal must be kept either refrigerated or frozen. Brown rice goes rancid quickly if stored in cupboard.
To prepare hot cereal: (1 serving/thick consistency*).
In small saucepan with 1 cup of rapidly boiling, salted water gradually add 1/3 cup scant of prepared brown rice cereal using a fork to stir well. *For thinner consistency cereal, either increase amount of water, or reduce amount of cereal. Continue to cook rice on high for about 30 seconds breaking up any lumps. Reduce heat until boiling subsides, cover pan tightly and simmer for 10 minutes.
Serve with your favorite toppings if desired. Season with salt if necesary. My favorite additions are toasted nuts, raisins and cardamom!