Suspension parts can and do rot when cars sit, miles aren't the only thing that destroys them. If they aren't dry rotted, don't squeak or creak, and the ride feels solid, and your *TRUSTED* alignment guy doesn't have a problem getting an alignment on it then I would leave it alone for now.
On the other hand if you're replacing one lower control arm and they both look about the same and you have no idea on the age of them I would just replace the other one too. You're going to have to get an alignment no matter what and on this car especially I replace suspension components in pairs. You could replace the strut rod to LCA bushings at this time since they have to come out to remove the LCA anyway and it's only $15 for both sides' bushings. If the strut rod to K-frame bushing doesn't look dry rotted or like it's shrunk and pulling away from the frame then leave it unless you're ambitious (it's not a fun job and some of the parts you need are obsolete and hard to find).