What is the UK standard E14 LED Candle bulb and holder for the US, is it E12?
E26 is used for most lamps in the USA. Incandescent bulbs have been available in that base for 120 volts rated in the range 7-1/2 W or less to 500 W or more. Today, the widest variety of LED bulbs are made with that base. The base is much larger than necessary for the most-used power ratings in incandescent bulbs. For CFL and LED bulbs that size base may more easily accommodate the required electronic circuitry. The most competitively priced LED bulbs seem to be the ones rated to replace 60W incandescent bulbs. The base insulating material and other parts apparently limit many fixtures to 60 W maximum incandescent. Thermal considerations also tend to limit CFL and LED bulbs to  the 60 W equivalent.

Most table and floor lamps are "double insulated" as required for use with 2-conductor, cords and plugs with no ground pin. I believe that the entire product needs to have an independent testing laboratory label such as UL or ETL.