"Now the Ruger GSR is a 1.5 - 2 MOA bolt gun in general. I base that statement on information from the scout rifle forums and from my own experiences with standard factory ammo. As with most bolt guns, some sand paper and acraglass will improve that. I have no idea what an M1A is capable of without the whole national match package, nor am I sure what to do about it if it not as accurate as I want."
Got my m1a loaded used for $1400 which is a fair price I believe. This rifle, unmodified, shot 2 moa with iron sights at 100 yards. I have now mounted a scope, shimmed the gas cylinder ($8 worth of shims and a very easy do it yourself job) and I've shimmed the sides of the receiver with card stock. I now normally shoot .5 to 1inch groups at 100 yards with federal gmm. This still just blows my mind. I mean this is a semi automatic battle rifle and it outshoots many bolt guns I've owned or shot.
So, I would definitely say get an m1a. Who cares about weight? Your talking about 2 guns or a m1a so I think your 2 guns would weigh more than 1 m1a. Go shoot one and make the call.