Considering a .308 Marlin versus a .300 mag !? You may want to reconsider your needs so you can focus a little more closely.
If elk were an occasional item, the BLR in 7-08 or .308 should fill the bill nicely. With bullets lighter than 200gr, the difference between .308/.30-06 is mostly in your mind, and I shoot both. A BLR .300 or .325 WSM is available if you really need a heavy. Avoid the BLR long action; handles like an 8ft 2"x6".
88 parts, and gunsmiths who can work on them, are becoming scarce. Triggers s***. 99's are coming near collector status.
The .308 Marlin is tied to its factory ammo, loaded by exactly one company and available in every rural convenience store? Handloads won't come close to duplicating velocity, at factory pressures. With a case capacity less than a .307 and factory blended powder unavailable, it can't happen.
After all of that, we're back to the BLR!