Wireless router in part of house, but need a hardwired connection in another part

I have a wireless modem connected to my main desktop in a downstairs room of my house (where my Comcast internet connection is located). The wireless connectivity is fine throughout the house for the most part.

However, if I want to connect to a slingbox to my tv upstairs which requires a hard wired ethernet connection, what are my options?

I will have no permanent computer upstairs.

Can I configure an access point for this or will I have to look at one of Cicso Power type options for this type of needed connection?

 

I have used Devolo for a number of years now and have found it to be a superb system, i can use a PC or TV anywhere in the house as long as there is a power outlet.

http://www.devolo.com/consumer/dlan-mains-supply-network.html?l=en