Plumbing - Thermostatic Mixing Valve (Wall)
American Standard Ceratherm Rough Valve Body with 1/2 NPT Inlets/Outlets, 9.5 GPM at 40 PSI
Available for about $125 (when HomeDepot has it on sale).
http://www.amazon.com/American-Standard-R510-Ceratherm-Outlets/dp/B00084RKLA $121
Check that it is low-lead.
Trim
American Standard Serin Single-Handle Central Thermostat Trim Kit in Polished Chrome
Trim available for about $63 (when HomeDepot has it on sale).
Or for $53 from
http://www.amazon.com/American-Standard-T064-730-002-Thermostat-Complete/dp/B001FBGIQS/ref=pd_sim_hi_2