Yep, those Marzocchi Marathon are priced fair and low maintenance. To ride the street and mild offroad, one shouldn't look for more travel.
Many would like high end long travel DH forks, but they are not improving a bike's handling if it doesn't have the geometry for this in the first place.
Keep in mind the maintenance schedule too. If you think that some forks are expansive, wait to see the cost of maintaining them in top riding condition. Taking them off a used bike that you bought for cheap can save you money sometimes, but often need frequent and expansive rebuild. Some forks that have been raced, or went through very hard riding conditions, have been rebuilt so many times that they will never ride as new anymore.
The best deals are new forks that have been taken off a bike for upgrade. I buy a new Freeride bike but don't want the stock fork, my upgrade leaves the bike shop with a new fork that have been installed on a bike, so can't be sold as new. After the season sitting on a shelf, it becomes "new old stock previously installed" and is often sold for less than half the price. When you want good deals on high end components, pay frequent visits to the specialty shops that are into expansive MTB, and buy off season when they need to pay the rent in the winter.