I've seen 3 in our (N.E. Texas) in the last six months for what I consider a very reasonable (750.00) price. One was a facebook post that just said "1895CB Like new 750.00 Paris TX.". I said I would take it before I even looked. It turned out to be an 1895 LTD III in 45-70. I was glad I had already said I would take it. The only thing I'm more of a sucker for than shiny guns is anything with an octagonal barrel.
I'd say it's "uncommon" to find one....I've NEVER seen one locally except a few gun shows. But never in LGS or pawn shop. have seen a few members here however that have. The price range is usually pretty wide as well, $650-$1500..so watch for the deals, because they are out there. Watch your local gun shows as well, maybe even travel a little farther afield than you normally would and maybe you'll get lucky. I have 4 JM cowboys, I've had to get ALL of them out of state from as far away as Washington state! '
Good luck! They are worth the hunt though!
One recently went for $715, in excellent condition. I'm watching one right now that has 6 days left and is at $515. I'm sure it'll go higher, but there is no Buy Now on it, so it'll be whatever the market decides.
I have never had much trouble finding one for sale and as other members have stated, the price ranges can be far and wide. Just keep looking and you will eventually come across one that meets your quality and financial criteria. I can tell you that I do not believe that I will ever part with mine as I consider it to be the finest lever action rifle Marlin ever produced, as close to perfect as you could hope for.