I think the simplest thing to do at this point is just call and get the v-code updated on the 505. If you were to change out the LNB then you would still have to phone in and get the v-code changed on the other 209 she still has.
If you are willing you could, as classicsat mentioned, change out her 209s for 600s. SD would probably give her some kind of a discount and a brand new style xKu LNB for free with a $50 install charge.
Also, you mentioned that hers was round and yours was oval. Did you mean the the satellite dishes themselves? If that's the case you will have yet another problem on your hands. lol
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