In a way, putting one together from parts as a project is not unlike putting a Garand together. The receiver is the easy part. After that, it becomes increasingly expensive and difficult to find the bits and pieces.
Ideally, a fine LB dark walnut stock set is desirable. Real barrels are rare. A .303 barrel lined to .22 is a viable option. A complete set of rear sight parts can take a bit of searching. A .22 marked magazine can be had; somewhat pricier than a .303 one. Most parts are the same as No. 4 parts, with the exception of those required for .22. If a .22 bolt head can't be had, a .303 can be altered.