Do we really know if it's the valve seat or the valve pin without inspecting it?
I just purchased a HP SS 30+ (I know slightly different gun) from a member here that has a broken valve pin. It's a 10 minute repair at most. On these semi-autos the pins can break, but the valve seat isn't a common issue AFAIK (although I had one previously for about a year and used it lots and it never broke, which is why I happily purchased this broken one for a good price). There is also this available which may be better than buying a $25 OEM valve pin from BinTac.
Common to all AEA HP Series and other PCP Air Rifle is the premature breakage of the Main Valve Pin/Steam and OEM design is common to all AEA, Benjamin, Kral, and others. This premature breakage is cause by the bending and impact loading on the valve as illustrated on Picture 07.
www.ebay.com
If it is the valve seat, OP will know when he removes the valve pin and it's not damaged. In that case, couldn't one fabricate a more robust valve seat from peak or some other higher-test materials?