@rogerg73 

If you already have some tp-link powerline units in the house, it is recommended to choose powerline devices with the same powerline speed for the best performance.

Here is a related FAQ to select powerline units: 2.There are TP-Link powerline devices in the house already

https://www.tp-link.com/en/support/faq/2725/

For the Wi-Fi feature, you could consider AV1300 wireless powerline unit, model TL-WPA8630(P). You may check the local store or retailer for this model, 

But as far as I know most powerline adapters are sold by KIT, you may need to consider a TL-WPA8631PKIT, which contains a wireless unit and a wired unit.
Both units could pair with your current AV1300 and work as extenders, but the wired one has no wifi, it could only works a wired extender.