Fully tested AC adapter HP-82026A for the Woodstock family of calculators. It is switchable from 110V to 220V but it only has the US plug.
The battery for a Woodstock calculator contains two rechargeable AA flat top cells. The batteries were produced by HP until sometimes in 1980s so by the year 2021 the youngest one is well past its prime at a venerable 40+ years of age. It is not difficult to refurbish them.