Better Shower Control Valve???

I understand what you want now. Unfortunately I think your pretty much stuck with RV junk for the wall-faucet.

Not sure why no one understands (except maybe Chris) what you are asking, but the shower control valve (the thing behind the wall where the hot and cold water lines connect) can be replaced with a standard household unit as well. You should have an access panel on the opposite side of where the shower control is located. Sometimes a false panel or a panel screwed to the wall in the other room (closet, cabinet?). Removing this will get you a good look at what you have. Take a picture of it and I suspect it's nothing special, just cheap. As long as you can get a new mixer valve that has connections in the same basic locations so the existing lines reach you should be able to do a quick replacement. If you want to post the picture here we could look at it and maybe give you some other ideas as well.

This item, LASCO 08-2471W Shower Head with 1/2-Inch Male by Female Pipe Thread and Volume Control Flow Adjuster, White Finish, will allow the hot/cold to be adjusted and then you can slow the flow of water or completely stop the flow of water without disrupting your hot/cold adjustments.

I actually just bought it as it went to an "add-on" price drop down to $4.75. Had it on my wish list and kept monitoring for a price drop as the regular price is not so good. The current price is even higher than the regular price I was seeing, so it should drop at some point. It is not made of plastic and seems very sturdy.

What you want is an "exposed pipe shower faucet" with shut off. They are very popular in Europe. Take a look at this one

http://www.lightinthebox.com/oil-rubbed-bronze-wall-mount-waterfall-rainfall-handheld-shower-faucet_p218947.html?currency=USD&litb_from=paid_adwords_shopping&utm_source=google_shopping&utm_medium=cpc&adword_mt=&adword_ct=200731637279&adword_kw=&adword_pos=1o5&adword_pl=&adword_net=g&adword_tar=&adw_src_id=2907233386_857974461_43048262546_pla-326887286578&gclid=EAIaIQobChMI4-im-J3K1QIVhANpCh0yUwOkEAQYBSABEgIdm_D_BwE

Try a real plumbing supply place- I know my old Airstream had a Moen single handle for the shower, which fed an appropriate fitting for the shower hose. IOW, it was 2 separate pieces, not all in one. I'm not sure if you will find a surface mount of higher quality.

I dont need a shower head. I need the thing that mounts to the wall and controls the ratio of hot and cold water.

Are you meaning the in-line shutoff that is normally standard on rv's? If so almost any thread on shut-off valve should do the job. Just ensure to use teflon tape and get it on tight (but not cracking it if its plastic). Even the cheap plastic ones Ive used on the past 2 rv's have held up no issue.

Just bought this one: Camco 43711 for our new trailer because the one that came with it dribbled like crazy.
It completely shuts off! (You'd think this was rocket sience)