Recirc ones are ideal for S-bodys still running MAF's or indeed any turbo car with a MAF so decent market on here or SXOC etc. Id say Silver one put it up for about £50 or so see where you go. The Black one wich is mounted to what looks like a S14/a or S15 hot pipe shouold fetch a bit more , i sold a similer set up all be it a Greddy DV for £80 so id expect you to get around that. End of the day its up to you what you want for them