For the price of a sporterized Lee-Enfield, it would probably be cheaper for you to buy another rifle than have the work done to replace the missing bridge. Look around for a good, used No.4 & you can pick up a B-Square "no gunsmithing" scope mount base & rings kit. For the absolute strongest mount option, you'll need to have the rifle drilled & tapped by a gunsmith. You might also keep your eye open for a commercial Parker-Hale or Churchill Lee-Enfield Sporter that already has been drilled & tapped and oftentimes inclused the base & rings.
As for your scope choices...I'd probably opt for something a little lighter, with less magnafication that is a little more practical for the .303 British round. Under perfect conditions, a 300 yard shot is doable on big game, but most users will be shooting at around 200 yards or under.
That said, I'd have a look at the Leupold VX-I & VX-II line, with something in the 3-9X40mm or 2.5-8X36mm range. They offer excellent light transmission & clarity, aren't overly heavy and come with a lifetime warranty. For the money, they're better built scopes than the Bushnell & I'm not bashing Bushnell, as I own a number of their scopes.
As for your scope choices...I'd probably opt for something a little lighter, with less magnafication that is a little more practical for the .303 British round. Under perfect conditions, a 300 yard shot is doable on big game, but most users will be shooting at around 200 yards or under.
That said, I'd have a look at the Leupold VX-I & VX-II line, with something in the 3-9X40mm or 2.5-8X36mm range. They offer excellent light transmission & clarity, aren't overly heavy and come with a lifetime warranty. For the money, they're better built scopes than the Bushnell & I'm not bashing Bushnell, as I own a number of their scopes.