Depends.
I subscribe to the thought process you should buy enough components to shoot out your barrel. That way you're out of components at the same time you don't have an accurate rifle anymore anyway.
That solves the "just in time" component availability issue.
There are other issues though: Case in point the 7mm-08 for long range target use. There is really only ONE bullet on the market that is well suited to a short action 7mm-08, and that's the 162amax (ok, there's the 162hpbt also but they're nearly the same thing). The other bullets on the markets are a compromise in 708; the 168smk sucks, the 175smk is too heavy, the 168vld is too long, the 180hybrid is too long and too heavy etc etc etc (I have high hopes for the 171 Barnes but haven't tried it so I don't know).
Even if they're plenty available, what if your barrel doesn't shoot them worth a damn?