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).
Check that it is low-lead.
American Standard Serin Single-Handle Central Thermostat Trim Kit in Polished Chrome
Trim available for about $63 (when HomeDepot has it on sale).