A British 1943 bronze Halfpenny (George VI), uncirculated and in absolute mint condition could fetch up to £6 GBP. If it has been circulated, not much.
The values quoted are the best possible for the best specimens in their grades, but may be significantly lower due to varying demand for the coin and the prevailing economic climate. A reputable coin dealer will be able to give a more accurate valuation based on inspection of the coin.
There was no British 1961 Halfpenny minted.
There were no 1943 New Zealand Halfpennies minted.
The British Halfpenny was made from bronze. If you have a gold Halfpenny, it would be because somebody has plated it. Modified coins have no collector value. Alternatively, if you have a very bright bronze British 1962 Halfpenny, see the related question below.
There were no 1830 British Halfpennies minted.
There were no 1832 British Halfpennies minted.
Such a coin does not exist. The last British Halfpenny minted for general circulation was issued in 1967.
Such a coin does not exist. Canada has not used the British sterling currency system since the mid-19th century, and has never issued a Halfpenny or half cent coin since Confederation. If the coin has no country name on it and has a sailing ship on the reverse, it would be a British Halfpenny. Alternatively, you may have a privately minted Halfpenny token.
Any Halfpenny coins circulating in Gibraltar in 1917 would have been British Halfpenny coins.
There were no British Halfpennies minted from 1828 to 1830 inclusive.
There were no British Halfpennies minted from about 1658 to 1671 inclusive.
An Australian 1943 Halfpenny minted in Melbourne, has no mintmark. An Australian 1943 Halfpenny minted in Perth has a dot (.) after the (Y) in PENNY (PENNY.). An Australian 1943 Halfpenny minted in Bombay has an (I) below the King's head.
British Halfpennies have not been made from silver for hundreds of years. If you have a 1939 British silver halfpenny, it is because somebody plated it, and it has no value. A halfpenny made from silver would be worth about £20 GBP just because of the silver content.