I know some online dealers require that the receiver of the ordered arm must match the one purchasing it. Classicarms.us and AIMsurplus.com come to mind.
What you likely will have to do is buy the firearm and have it shipped to Virginia where you take initial receipt and then have them ship it to your father's FFL. You'll have to pay for two transfers that way.
I'm not that well-versed, so there may be another way around it.