Well I got the Spray Away from local dealer and with gift card. They are not cheap but you can opt for just the connection and store the hose in your "basement." But there are several on ebay now:
Phoenix Prod SA 15 BTW Sprayaway Selfstoring Sprayer w 15 039 Quick Connect Hose | eBay
Pheonix Products Website:
Look in the "outside" category.
Shower was online store from:
classacustoms on eBay
Plumbing parts from Home Depot but you may get the plastic fittings cheaper at a real plumbing supplier or at your RV dealer.