I was going to suggest that, but the work involved in fitting a new forend (or even a 'pre-loved' forend) can be as much as repairing the original.
I replaced a forend on a No1 Mk3* and had huge problems - the most difficiult to resolve was that with the new (old) forend in place the rifle would not fire - without it, fired no problem.The new wood was 'fouling' the trigger assembly, I tried with a forend of a No1 Mk3 in 410 calibre and it worked perfectly, put the other forend on the 410 and it also worked perfectly.
Every rifle is an individual.
Remember that these rifles were the last of the 'Victorian engineering, hand built' rifles (unlike the No4 where most parts were interchangeable) and the wood work has to be FITTED to each individual rifle.
There are 5 important parts that must stay together and these were numbered by armourers (if they were not already numbered) these were :
Bolt
Barrel
Rear Sight
Nose-piece
Forend.
Replace any one and the rifle had to be re-worked to get accuracy back again.
From the 1931 issue of "Instruction to Armourers":
1. General.—Examine the rifle to see that the number, and the series letter where marked, on the
nose-cap, fore-end, sight leaf, barrel and bolt agree with the number on the body, and that the rifle is
complete. Record deficiencies, if any and damage due to unfair wear for report.