He'd be better off buying a cheaper rifle and spending money on upgrades to bring it up to that price, there's nothing special about the VFC 417 that'd make it overly DMR worthy.
I'd recommend an SR25 of some description with some basic gearbox upgrades done to up it past 400fps, then a good hop unit, rubber, nub and barrel.
AFAIK no DMR is going to be good OOTB. Like a bolt action rifle it needs a lot of upgrades to be any better than the ordinary AEG. You would want to upgrade the hop and inner barrel anyway and that should give good accuracy and range.
TM high cycles have max effective ranges of 40m. They only fire 250 FPS,they have a short strokes piston so less air volume which means no joule creep and IIRC their hop up units are different. 70m range is bullshit for a high cycle,they;re built for reliable ROF and not range+accuracy.
Anyway,the best DMR is one you built yourself. CYMA,G&G and G&P m14 series are good since the version 7 gearbox is very reliable. VFC 417 is known to have a weak shell. A stock TM won't do since it's performance won;t be as good as a basic/budget DMR built well
G&P M14 is a very good choice. Bar the gearset & motor the internals are quite good,especially the hopup. CYMA make a decent SVD but they have tolerance issues and may not take the realsword parts they clone.