I have read on this site that the original green firing valve seal is junk and needs replacing. My Walther is a very early one with the original green seal on the firing valve. This seal is the original factory fitted and is still working 7 years later. Sure I see some temp shift but it is only like 10fps slower on hot days compared to a cold one. So my question is, are they really that bad? And where would you get a replacement from? As these seals are pressure parts do they fall foul of the law and require a face to face? As I know none of my local gun shops have little to no knowledge of Walthers.