Green’s Dictionary of Slang

to pay over money, to pay on demand.

1821		‘An Amateur’ Real Life in London I 559: Many a twelver † does he get by buying up broken images of persons who sell them by wholesale, and he of course gets them for little or nothing: then what does he do but dresses out his board, to give them the best appearance he can, and toddles into the streets, touting†† for a good customer. The first genteel bit of flash he meets that he thinks will dub up the possibles,? he dashes down the board, breaks all the broken heads, and appeals in a pitiful way for remuneration for his loss; so that nine times out of ten he gets some Johnny-raw or other to stump up the rubbish [? To dub up the possibles —To stand the nonsense — are nearly synonymous, and mean — will pay up any demand rather than be detained].
1836		H.M. Milner Turpin’s Ride to York ii 5: sam: Peel my skin and dub up the browns! What do you mean? bal.: Just this – that if you do not hand over your money I shall blow out your brains! [F&H].
1844		C. Selby London by Night I i: I must provide our dupe with dress, cash, and all the requirements of a gentleman – so dub up!
1845		Bell’s Life in Sydney 6 Dec. 3/3: On entering Driscoll's yard [...] he cried out ‘dub up you black b—r’.
1852		G.C. Mundy Our Antipodes I 181: The juniors are compelled to dub up, or are seized and robbed by force.
1873		Sl. Dict.
1881		N.Z. Observer (Auckland) 15 Jan. 169/1: The Rev. Mr. G. [...] flatly refused to dub up.
1881		Newcastle Courant 2 Dec. 6/6: Here’s the wash and if yer please Mrs Maguire says as how she would take it kindly if yer would dub up — I mean pay her at once.
1881		N.Z. Observer (Auckland) 22 Jan. 181/2: Whether Mr. Gittoes was or was not asked to ‘dub up’ [...] 15 per cent of his salary remains to be proved.
1885		Bulletin (Sydney) 14 Mar. 7/2: For if it be necessary that the railway officers should dub up a week’s pay, it follows that every other toiler and capitalist in the colony should do the same.
1891		Sporting Times 21 Mar. 1/4: Unless Nathaniel dubbed up ten of the best he would be locked up in the Chateau Lambert as a rogue.
1895		Crowe Aus. Sl. Dict. 25: Dub Up, pay up.
1901		‘Miles Franklin’ My Brilliant Career 259: None of us have a penny to bless ourselves with, let alone dub up for taxes.
1908		Gem 17 Oct. 4: A giddy baronet ought to be able to dub up at times.
1954		Oh Boy! No. 17 14: Now then, Ma! Dub up! This is a hold-up!
1980		Barltrop & Wolveridge Muvver Tongue 21: Callin on some one to disgorge cash, the phrase is ‘dub up’ or ‘dub out’.