OID value: 1.2.826.0
The rules for assigning OIDs at a national level in the UK are given in BS 7453 Part 1, section 6.
For organizations registered as a company under the provisions of the Companies Act 1985, section 6.1.1 states that the company "is deemed to be assigned" an object identifier that starts with 1 for England and Wales, 2 for Scotland, and 3 for Northern Ireland, and has as its next component "the integer value of the numeric component of the registered number". So Viking Direct Limited, having the registry number 2472621 in England, would have the implicit OID 1.2.8126.96.36.1992621 assigned to them.
The Peer Association Limited has the registered number 27371R; the "numeric component" part would assign them 1.2.8188.8.131.52371; I guess the people who wrote BS 7453 thought this was an unique number.
In addition to this, BSI can register OIDs directly under the 1.2.826.0 branch; they have started assigning numbers from 1000 and up, more or less arbitrarily. Ray Walker <Ray.Walker at BSI.BSI.gold-400.gb> knows more about this.
See also the OID Repository website reference for 1.2.826.0