Pentax 67: Four LR44 as replacement for 4LR44/PX28/A544/476A battery
LR44 Lithium Battery Equivalents
Amazon.com: AmVolt- Pack of 15 LR44 Batteries AG13A76 Battery, Premium Alkaline Ultra Power Non Rechargeable Button Battery, 1.5 Volt Small Batteries for Remotes Games Controllers Toys & Electronic Devices : Health & Household