Last NOS one Ive seen was on ebay in 2017 or 2018. I bid $275 on it and if I remember correctly it went a bit over $300. Factory 4 speed cars have a larger mounting bolt spacing on the 2 bolt boot. Guys who convert to 4 speed can use the 70-81 camaro boot, just drill a smaller pushrod hole for the Z bar rod. I have a factory 4 speed car and was in this dilemma as well. I bought the camaro boot because its the same with the exception of the mounting hole spacing. I took my original mounting plate, removed all the rubber on it and traced it on a piece of 1/2" plywood. Cut it out, lay in the original plate, lay the camaro boot on top of it while aligning the bottom mounting screw hole with each other. Then fill the remainder of the void in the plywood with Permatex Ultra Black. Smooth it out nice and level and smooth on the camaro boot. Let dry a couple of days. Remove it and it looks real good. Only difference is that the mounting plate is a bit thicker than original. Good luck with it.