unidentified civilian uniform buttons

[btns]

My tray of unidentified British buttons has grown over the years. I am presenting them to the forum hoping for an ID.
Thanking you in advance.

001: dolphin, white metal, 23 mm, Firmin, London & Birmingham
002: it could be a livery button; gilt 25 mm, b/m not recorded
003: I have no idea what beast this is; I guess it is holding a mace, not a German handgrenade, gilt 29 mm, Made in England.
004: monogram letters C.S. in gold and green. flat, Gilt 19 mm, backmark not recorded
005: monogram I.H. (different from Internation Harvester buttons), gilt 24 mm, Dowler, Birmingham

[btns]

The next lot of five buttons ...

[btns]

Here are 5 more unknown buttons:
15. monogram letters A.L.; Gilt 25, backmark: Special Quality
16. letters U.S.M., Chrome 25 and 21 mm, backmarks: Wm. Dowler & Sons Ltd, Birmingham and Dowler, Birmingham
17. monogram letters L.C., silver plated 17 mm, no backmark
18. a logo(?), chrome 20 mm, backmark: Dowler, Birmingham
21. a mess dress button: crossed axes, SP/Gilt 16, <greek key design>

[btns]

Another 5 unknown buttons.
19. D.M. & T.T. Co Ltd, white metal 24 mm, Special Quality
20. D.M.S. & N. Co, white metal 23 mm, Fast Shanks, * * *
22. monogram L.W.R., gilt 25 mm; Pitt & Co, 31 Maddox St, London
23. A.W. & Co, Gilt 25 mm, b/m not recorded
25. L.H.P., brass 19 mm, b/m Superior Quality

[btns]

and 5 more
26. castle, gate or church, letters G.R.C., G17, backmark J. Smart, 32 Walbrook (In 2010 it was on the (now defunct) golf buttons website by (the late) John Sagi)
28. monogram O.M.S., chrome 26 mm, b/m Emeralda, Cardiff
(I have searched for 'motor services' e.g. City of Oxford Motor Services, but never found evidence)
29. old english letters or text 'Philorth', gilt 16 mm; Firmin London
31. monogram letters C.T.C., Gilt 14 mm, Buttons Limited <crossed swords>
32. engraved letters O.D.S., gilt 19 mm; no backmark

[Hawthorn]

You mention that button 26 appeared on a defunct Golf Buttons site so instead of GRC it seems more likely RGC, as in R... Golf Club.

Unfortunately many areas use the Castle or Church as you know, have checked local Clubs to me and the nearest similar is Reigate but the Castle on there arms has only two Towers so no link.

Not much use I'm afraid but enjoying viewing these items.

Regards Simon.