regarding the 243 WSSM. Most people would rather gear themselves up for something leaning towards a 300 RemUM or something of that persuasion...lol I have a 243WSSM and it was Browning's and Winchester's best kept secret. Mind you mine is a Medalion and not a varmit, or target rifle, and shoots very, very well.
While they are not in production at the moment, you might be able to persuade (beg) Browning to produce one (last one) for you in the A-bolt. If they do it for you, you'll be good to go. If not, you could try and get the 25 WSSM it would be a good choice too.