Looking for 7.20" push rods...

What you need is a ball/cup pushrod for an adjustable rocker/hydraulic lifter combo, which is about the length you mentioned. Only the 340 6-pack engines came with them as original equipment.

273 pushrods are too long because they had solid lifters - 7.5". When they switched 273's to hydraulics, they also got the stamped rockers. The 7.342" pushrods are advertised to work with hydraulic lifters but I found them to be too long also.

You'll need to do some research for part #'s. Summit has some good search features for parts. Crane had the right length but don't know if any vendors have any leftovers. I don't have the part # handy at the moment.

Be careful because there are 2 ways to measure:
1) Overall length - tip of ball to top of cup.
2) Effective length - tip of ball to bottom of cup.

I think the "effective" length is usually used.