My 97 Stumpjumper (8 speed) is coming out of retirement and I need some help with some driveline questions.

Current:
Strong arm crank w/ 42/32/22, chainrings badly worn
Cassette: 12-30, more than likely worn
Chain: worn
RD: XTR, seems ok...maybe shifting down a little slowly
Shifters" XT 8speed, seem fine

Is it reasonable to change just the chainrings, cassette and chain and go with it and if the RD has problems then get a newer XT 772 shadow.
Is this problematic?
or...
Just get a new 9 speed set up?
LX 582 Crank, XT 772 RD, XT shifter, XT 9sp cassett, 9spd chain.

I realize the top option is cheaper ($125) versus the bottom option ($450-$500), albiet everything would be new...and I plan on keeping this bike for a while, there's always trails for a HT.
Spending the money on a 9spd set up isn't really a problem for me, but not if the 8 spd upgrade will work and is easy to find.

Thoughts.