Green’s Dictionary of Slang

snakes and sawdust! excl.

(Aus.) a mild excl.

1867		Dalby Herald (Qld) 20 Apr. 3/2: There stood [...] hammer in hand, and puffing like a steam engine, a loquacious auctioneer, selling off — oh, snakes and sawdust! it busts my heart to mention it— the ‘Dalby Club’.
1887		Bulletin (Sydney) 15 Oct. 9/2: [A]t last the dazed and dusty wanderer, speaking from the recesses of his full heart, murmured, ‘Snakes and sawdust, what a saint!’.
1897		Coolgardie Miner (WA) 27 Nov. 7/5: John Bull does get a few plums, but, snakes and sawdust, what a lot of stones he has to spit out.