Welcome to the site and congrats! I'm no expert on this, numbers made, all the features over time etc., but don't believe they (18 rnd mag) are really rare so to say, but to many somewhat sought after and held onto if having one if you know what I mean. I believe at one point the state of NJ changed a law to limiting rifles in their state to 15 rounds, so Marlin changed the design to avoid issues selling there. I can't recall the year off hand though, and maybe somebody smarter than me will come to help. Enjoy that rifle...

 

I don't know how rare they are, but yes, that combination of the long barrel, long magazine tube, and LSHO was only made for a short time, and they are desirable. Congratulations! Got any pics you can post?

 

I can sure post some tonight. We took it shooting yesterday and it jammed on a few rounds. Last night I completely disassembled it and it was pretty dirty inside lol. Got it all cleaned up, took 2.5 hrs but very clean now!

 

I'll agree with the above. While not rare, the long barrel, long mag tube and LSHO are more desirable for some. Most will say they started in 1985 (s/n 15xxxxx) but I have a 1983 (s/n 17xxxxx) with the long barrel, long mag tube but no LSHO and a 1984 (s/n 16xxxxx) with long barrel, long tube and does have the LSHO feature. I also have a 1987 (s/n 13xxxxx) in the middle of a stock refinish with the same combination. I don't know exactly when the mag tube was shortened to comply with the NJ law, but it was sometime in the late 1980's, obviously post 1987.

What are the 1st 2 digits of your serial number? That will tell the year.

As far as value, probably all over the map. Over the past 3 years, I have been able to get nine older Marlin's around here (New Hampshire) either in an auction (5), LGS (2) or private sale (2) ranging from a rusted basket case 995 to a pristine with stickers 60SB. Prices ranging from $63 to $126 out the door. With an average price of $93.69. The '84 Model 60 was $86 (auction) and the '87 was $75 (private sale). Stocks were beat up on both, paint on the receiver flaking, light surface rust and were so filthy the bolt wouldn't lock back on one of them, one had a broken magazine follower. However, they both cleaned up nicely.

Here's the '84 vintage.

 

Desirable, but not all that rare. LSHO was introduced in '85. I've seen the 18 rd mag on Model 60s as late as '90.
Mattherw, if your serial number starts with 15xxxxx, it is an '85.

 

My 1987 long barrel, long mag tube, LSHO unfired new was $175 this past summer off a consignment rack. Not rare, I've been scoring at least two a year in new condition, other this year was a NIB 1978 Glenfield, she was had for $135, couldn't get my wallet out fast enough.

 

Mattherw, if your serial number starts with 15xxxxx, it is an '85.

Typo, I edited to be 16xxxxx. Thanks!

 

The serial # is a 15xxxxx. I traded a PS3 for it, figured it was a pretty good deal.

 

I see you have the Williams Fire Sights on that. I installed those on one of mine as well. They work great when there is light. However one range I go to has covered booths that get rather dark, and there is not enough light for them to collect.

 

P-bass - yes, they are the Williams Fire Sights. You are right, in general - awesometacular, but reduced effectiveness in low light.