I bought a B18 from Joe G. and then traded him for the 712. Here is photo of one if you are not familiar with them The one in the photo may be Siffert's old chassis.
He had another buyer for the B18 who was willing to pay enough that I got the March straight across with no extra money. (Very unusual for any deal with Joe G.)
The 722 came with a Hart motor as well.
And if you remember the BDD
kits were 5.5 K. Way rich for my budget back in the day.