As noted, your 1979 is pre-safety, but the issue is not one of quality, it is simply that many people (purists?) dislike the cross-bolt safety, and are willing to pay a premium for an earlier 1894 without one...
The real quality issues have come in the last 15 years or so...Marlin seemed to be in a slump, and then to worsen things, they were purchased by The Freedom Group who moved all production of the 1894's to Ilion, NY...
The results of all this have been to drive the prices of used Marlins up, and especially good condition pre-safety models...
You have a VERY nice gun, and it will serve you well for your lifetime...
As mentioned, the bores tend to run a tad large...Mine wants .430" jacketed bullets, and at least .431" cast...