I recently purchased a Marlin 1895GS, and one of the things I was adamant about is no ported barrel. I had a look in the dealers 2004 catalogue and there was no mention of ported barrels there. This will tell you the change was made prior to twelve months ago.
There are still ported barrels out there, so you'd be well advised to ask prior to purchase, if you are ordering sight unseen.
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