I have ended up with several wood stocked hunting rifles that needed the sling attachment studs redone - drilled to be crooked to centreline of the stock, not installed at right angles to the surface, or way too close to the tip of the recoil pad / butt plate for my taste. From several factory rifles here - appears 2 3/4" to 3" about "normal" distance for the rear stud to the tip of the butt plate or recoil pad - I have seen pictures of English (?), German (?) sporting style rifles that the rear sling attachment might be 6" or more from the rear - and they look like they belong there.
I do not know what is the "correct" distance from front of the fore-arm tip - I have seen pictures of some rifles with front sling swivel installed to the leading end of the forearm - but never used or owned any like that, except a BPS shotgun that got carried a lot of miles for prairie chickens. Is some rifles with short forearm that the stud is attached to the barrel - I think that was for using the thing as a "carry strap", not as a "shooting sling".
Out here in the boonies, I have seen rifles done up with the sling swivel bases from No. 4 Lee Enfield and similar - the base parts usually inletted into the wood - then fastened with two wood screws - and same unit used on both front and rear - I think makes super strong set up - but about no sense on a "sporterized" two piece stock that only has one "King Screw" holding the forearm in place.