What dish for a HDR10-250 and a THR22

Trying to help out my father-in-law here. He has two TVs in his house on one he has the older HR10-250 and on the other he now has the THR22. He still has the older 18" round dish, he hasn't wanted to upgrade that yet. He does have an antenna as well and gets all of his local channels through that in HD.



My question is what dish will work with both of the above Tivo units to provide the standard directv signals to the HR10-250 and then the full HD content for the THR22? What all do I need to make sure I have for him to get this working?



Thanks for the help.



Phil