I added one to our 348. I found a coil hose that fits inside it's own storage enclosure.
This one: http://store.oceanequipment.com/Product ... ctid=HE15F
Sorry, don't have a picture of the one I installed, but this gives you the general idea:
The enclosure is round and is narrow enough that I cut a hole into the anchor locker hatch and installed it there. So I can pull up the hatch, with the hose container in it, and still get into the anchor locker. I used some hose on the bottom of the container to give me enough slack to pull it out without having to disconnect it. I then ran some of the Whale plastic tubing into the fresh water system.
Yes, I use fresh water to wash down the anchor. I figure it takes about a gallon to blast the mud off the anchor. The fresh water pump has enough pressure to do the job. That doesn't put much of a dent in the water available on board. That was a LOT easier than installing some sort of seawater pickup with it's own pump.
I also added a short drain hose under the enclosure (it has a fitting for it) to direct the water toward the anchor locker drain. I've accidentally left the hose turned on and had friends in nearby slips point out the water draining out the anchor locker. I also forgot to winterize it properly the first year and cracked the nozzle (but it was easy to replace since it's just a garden hose fitting).
So if you've got a round hatch or a flat spot large enough for the enclosure it's a modification well worth the time/money.