I had a suspicion but had to confirm it. I never realized that all the dipsticks are the same, except the Hemi.

This picture is from a unmolested 1970 -440/727, race 1974-440/727 and an all original 74-318/904.

The 70/71 parts book lists 1 part number for all engines EXCEPT the 426 but I think you may know that already.

If your dipstick number is correct then it isn't for a Hemi but the fact it has rivets may indicate somebody modified it.

The dimensions for thee dipsticks are 18" from the staked spot under the seal to the tip. About 18-3/4 from the top of the seal to the tip and about 21.5 overall.

At the end of it all I think you will need to measure how far the stick extends into the pan and compare it to any other 727 transmission.