Yes trying to find a burial in London is very time consuming. I found out some when Ancestry released a lot of the LMA records but there are still many to be found.
The date of death is the best thing to go on first.
LONDON, Coombs, Roberts, Auber, Helsdon, Fradine, Morin, Goodacre
DORSET Coombs, Munday.
NORFOLK Helsdon, Riches, Harbord, Palding
KENT Roberts, Goodacre
SUSSEX Walder, Boniface, Dinnage, Standen, Lee, Botten, Wickham.
SUFFOLK Titshall, Frost, Fairweather, Mayhew, Archer, Eade, Scarfe.
DURHAM Stewart, Musgrave, Wilson, Forster.
SCOTLAND Stewart in Selkirk.
USA Musgrave, Saix.
ESSEX Cornwell, Stock, Quilter, Lawrence, Whale, Clift.
OXON Edgington, Smith, Inkpen, Snell, Batten, Brain