I've seen them as low as $7, but some look 'cheap'.
https://www.shopgoodyy.com/products/...iABEgL_5_D_BwE
The ones from UroTuner don't look too bad:
https://www.urotuning.com/products/u...=8311005184055
Yeah, just search 'O2 Defouler' or 'O2 Spacer' and check results.
I prefer the ones without any media or 'baffles', but suspect they would work too.
EDIT: Danny C. from the efi forums recommended the Innovative ones, and grabbed a couple of those. I have some others too, but just wanted some on hand.
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1970 GTO Judge Tribute Pro-Tour Project 535 IA2
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1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car
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