There are beech wood stock sets on ebay for the No4Mk1. I might add, many parts too... Heck even some No1MkIII* stock sets, but made in India with the ishy screw.
The issue is when people sell these off and don't tell anyone it's a de sporterized rifle. The quality of the reassembled rifle is also subject to the quality of the parts used.
Like damaged screws, scratched up barrel bands, milled vs sheet metal parts. Mixed metal finish like phosphate vs suncort vs blued. Obsolete components on a rifle that
would never have a 300/600 yard sight on it if it was FTR'd in 1953 in the UK. In some cases, I have seen attempts to put long range dial sights on a post 1920 No.1 MkIII stock pattern.
Do it right, Do it well. Just to add, that's why allot of fellows who restore firearms have alot of surplus of parts on hand in there workshops.