If you are looking to replace the head or repair it, Toro does not sell the head / motor separately. They do sell the spool and its related parts. Some Toro trimmers are the same as Kobalt trimmers so sometimes you can find Kobalt replacement parts that will fit although they are the wrong color. https://www.partstree.com/models/51...fTLr4pEsQwh03CSN-M5_WdWGcpP2ko9BoCwqIQAvD_BwE
If you are just looking to refill it, the video link posted by Auto Doc's is worth watching.