I've a Lee Speed project in the works. It's on the back burner now as I've moved a Mannlicher-Shoenauer project to the front burner. I'll be getting my stock from Australia. In the US, Great American Gunstocks has the patterns, or did have once, for Lee sporter stocks. They aren't a cataloged item. You might give them a call, as they don't respond to email well. The charger bridge can be removed from a SMLE and TIGed to fill the rivet holes. A No4 Barrel will interchange with the No1 barrel, it will be 180 degrees out of time, however and the extractor slot will be on the wrong side, and the flat on the bottom. However, the No4 barrel could be copied and threaded, allowing the extractor slot to be cut when appropriate. A No4 contour would be more appropriate to a .375 bore. Even if going with 303, I think I'd rebarrel just to get a sporting chamber, and not an oversized military chamber. I haven't found a source, or good information on correct sling swivel eyes. There's a lot to consider when trying to do a replica.