Can't help with sight recommendations, sorry, but would like to add that I bought a Ross M-10 .303 in standard military form many years ago, specifically to find out first-hand about this 'dangerous bolt mis-assembly' thing. I have to agree with xausa, in that you would have to be a complete dunce to mis-assemble the bolt in the first place, and then to not notice this condition when chambering a round....? Well...! And this applies to the 'local gentleman' in your home-town too, 9ThreeXFifty7!

Obviously some of the Canadian conscripts were none too bright either, as deaths are recorded, so a fool-proof modification consisting of a pin through the top of the bolt was introduced (in 1912?) to prevent this from happening. Certainly, all the ex-mil Ross rifles sold in the US after WW2 have the pin, according to Stebbins. This might be a useful modification to an M-10 sporter if you were really worried, but I suspect it would harm the collector value. If you are already milling for sights, though....