https://www.pololu.com/product/1924 here are standard servo connectors (male)
https://www.pololu.com/product/1902 and here are the 1x3 dupont housings.
The servo connector housings are a bit slimmer to make it easier to plug into receivers.
https://www.ebay.com/sch/i.html?_fro...t+kit&_sacat=0 Kits like these with dupont connectors of various sizes are less than 8 USD on ebay. You may also want to check out the pre-crimped "dupont jumper wires" that are very popular with arduino fans. You can easily tear off what you need from the ribbon cables and swap the 1x1 connector housings for 1x2 or 1x3. They usually come in 10/20/40 cm lengths and male-male, male-female and female-female types.