Budget build on the cheap

I found a guy on kijiji in my city selling thermal quads model #9057S,model#9046S,model#9100S.The other 2 are older model#3826S and model#4966S.. Are any of these worth putting on to substitute a 750? He wants $15 a piece or $50 for them all. I am sure they would need a re-build.

these carbs would help keep my build on a super budget.

Are any parts of these carbs interchangable?