Copper wire re-inforcement is not strictly Indian. It was done also in Australiaand in the UK
, though the UK primarily did this mod in WW1, it continued to be done in small batches up to the 1960's or so.
If you go to the technical articles section, there is an article there from Peter Laidlerabout these guns.
These guns are identical to any other SMLE, except that they are re-inforced with wire for grenade launching with the use of the discharger cup. This is so that in the unlikely event the stock shatters, the firer won't be wounded.
You can shoot ball, or any other safe .303 ammo in these guns. No problem. Assuming hte gun is in good repair, that is.
As for replacing the wire, it can be done if you can find sufficient qty of the correct diameter wire. After that, it's just a matter of re-wrapping the wire the same as it came off and re-soldering the ends, usually for 6 rows of wire.
As a trick, to solder, use flux and heat the wire itself with a torch, then the solder will flow by itself and you won't burn the stock all to hell.
As for bores, some are worn, many are like new. Depends on the specific rifle being discussed. My example has a bore that looks unfired. The discharger cups now sell for $100+, not sure why.