Bummer on the stud find. Great choice on head studs. If you don't know how many miles are on the engine, have the valves and guides done. Sound like this engine has more miles than you thought. If the cams and rockers were good then playing the odds the bottom end should be good. Judge it based upon how much wear was on the top end.
Most bottom ends are good for 200,000-250,000, if the engine has been well taken care of. I did a full rebuild due to two broken studs. Parts are not a lot more to go all the way but there is cleaning, balancing, polishing and all the extra labor/time. Some decisions based upon the wear that you can see on the top end generally is similar on the bottom end. The other is cost. How much do you want to spend?
My rebuild was great fun to do and the engine is much stronger due to a few performance mods and larger P & C's.
