The AIA rifles on the Marstar website are the only modern production/repros that I am aware of. The LE action will never support hotrod handloads as well as a front locked action, having said that, with tight chambering & proper control of reloaded haedspace they are still capable of being reloaded numbers of times if pressures are kept to sensible limits. I think the factory pressures in 7mm-08 & 260 Rem are as high as I would want to go in such a firearm & that was only assuming that all else was in perfect condition. Britain used No1 Mk4 rifles that were converted to 308 for many years as training target & sniper rifles so the basic design must be strong enough. Many years ago when I queried getting such a conversion done I was told the No1 Mk4* rifles from Longbranch in Canada (?) were the prefered ones to do this on, something to do with the metallurgy in them, but the British ones were just normal production ones, possibly crack tested, who knows. The AIA rifles are based on the No. Mk4 design which is significantly stronger than the SMLE Mk3s, other the the later Indian ones but thats a whole other subject for someone else.
Steve