Anything is restorable providing that you throw enough time and money at it.
For a military style rifle, this might not be a good one to use as the base for a rebuild. The barrel has been permanenetly modified, so to get it back into a military stock and looking right, the barrel will need to be replaced or repaired.
If you had the expertise, not a problem. The barrel change is a straight forward process. However, it requires special tools, gauges and often a lathe, not something for the home mechanic. You will need to pay a gunsmith for shop time. A good used replacement barrel would have to be found. Good luck.
Criterion are making new high quality replacements but the cost is up there. So unless you were building a competition target rifle or similar, not really viable. You would spend more money on restoring it than it would cost to buy a complete and original example.
But it is your money. Restoring can be a lot of fun or frustration or both.
I am into restoring, so will give you every encouragement to have a crack at it, but must warn that it can be a rough road to travel.
Your rifle is what it is. It is a classic sporter Lee Enfield, rugged and reliable, it will get the job done. Try it, you will enjoy shooting it. Ammunition can be expensive, so all the serious shooters that I know hand load. That is a hobby in itself as each Lee Enfield likes ammo tuned to the rifle. One can get some surprising results just by playing with different loads and bullets..
If you want a military rifle, I would respectfully suggest that you go find one that needs less shop time than this one.
Replacing the wood also requires some black magic to to get it stocked up right. It is not a drop in fit, each has to be hand fitted. This fit of the wood can have a severe effect on accuracy.
Thinking of restoring this one is similar to buying a zooped up hot rod car and then thinking to restore it back into a 1925 Ford T saloon. It can be done, but a lot needs replacing.