It would not be that big of a deal to switch it out.
You can buy all the parts at midwayusa or brownells. You will need a new floorplate and actual magazines. That should be it, though it might require just a little stock work, but it shouldn't be much if it does. It'll set you back about $100 for the parts if you go with remington factory stuff.
Ive been curious about having my favorite LTR mag switched out to accept M-14 mags... would that be just as easy and around the same price as to get my LTR to accept the Remington DM mags? (whatever mags they use i have no clue... and M-14 mags are plentiful for me)
Unfortunately, no. Robar does a M14 mag conversion, which is about the best one out there, but it still really isn't very reliable because its not a center feed magazine and its fairly expensive. If you wanted to go with an extended mag, about the simplist and best engineered is the one by HS Precision which is a center feed mag. It is a simple floorplate swap out. Price isn't too bad, the SC price would be $233 plus a bit for shipping. That includes one magazine. Both the new floorplate and the magazine are stainless steel.