I really like this idea and want to build one myself. I've not found that portable shower head anywhere yet though.
I love when different parts coincidentally fit together perfectly! Great build thread for something so simple.
I would be surprised if that filter lasts long at all though. using a paper fuel filter should clog up very quickly. water in a fuel line will clog any fuel filter by making the paper swell and close off flow. you would be better off using a pond type pickup filter. they tend to be made of brass or ceramic and porous at a very small micron level.
Here is an eBay link the item is in Hong Kong. I ordered from the same seller the shipping was pretty fast and I have been happy with the shower head.
http://cgi.ebay.com/CAMP-SHOWER-FISHING-HUNTING-PICNIC-BOAT-ACCESSORIES-KIT-/230638777826?pt=LH_DefaultDomain_0&hash=item35b32475e2#ht_2711wt_1111
That is the same shower head Helton sells.
I just found another source here in the USA. They sell the full Helton kits. They will also sell the parts individually.
http://www.cruiseroutfitters.com/helton.html
I use a similar idea but different if that makes sense. A 20l black plastic drum. Leave it out in the sun all day nice and hot. In the kid I drilled a hole and then got a inner tube and cut the valve stem out with enough of the tube to fit inside the lid. Then used enough glue/silicon to seal it up. Piece of hose and a shower head.
Hook
The air compressor up
To the valve and away you go, pressurized solar hot water.
pictures?