Unless you're trying to do a factory correct resto, the length of the tube and dipstick are irrelevant as long as they are set up to read correctly. The key is to make sure the stick is not too long, and that it measures oil level accurately.
If you want to restore it to factory, that's fine. If the issue is your tube was shortened and you don't care about that you can make a new dipstick easy-peasy. I had this exact situation in my 66. I got a dipstick that's longer than necessary to start with, mine was a whopping three bucks at the junk yard. I put the stick in the tube until it bottomed out on the oil pan and measured how much was sticking out above the top of the tube. I cut it a half inch too long and did a second test fit. The stick was stopped from seating by a half inch. So I then cut the final 3/4" off and I know the stick stops 1/4" above the bottom of the pan. I changed the oil and filter but only added four quarts of oil. I ran it for a bit to fill the filter and then shut it off to take an oil level reading. That is my one-quart-low mark. I scribed that with the edge of a file, then added the last quart of oil and measured again. Another score mark with the file and done. It takes longer to describe that it did to do the work.