To answer your question about the scope - accepting it is a 1944 rifle, then pretty much any mark. The scope number on the butt relates to a 1941 production Mk1 scope by William Watson. If the butt turns out to be original to the rifle then that's your answer (though that would be rather unusual).
However, if it is not the original butt, then we return to what is appropriate for a 1944 4T. The Mk2 scope was introduced in April 1943, & the Mk3 in October 1944, so both Mk2's & 3's would be acceptable, as would the hybrid Mk2/1. But as I mentioned above, Watson continued producing Mk1 scopes into 1944 (they tend to turn up with serial numbers in the 14,000+ range), so a late Watson Mk1 would also be acceptable. If you intend to shoot it at all regularly I'd try & find a 2/1 or a 3, simply because they're less fiddly to adjust.