Does anyone know if any other engines would "hot swap" or with little effort, fit into 06 heritage softail efi?

Here's my original dilemma. https://www.hdforums.com/forum/softail-models/1413591-06-heritage-front-cylinder-clatter.html

Manual states it is a 19259-06. Seems like a short lived engine production.

Thank you very much. I'm trying to find the best solution with the least expensive hurt to my pocket. In reality had this bike not belonged to my pop who passed away in 2018, I'd probably dump it for parts. However... it's now a sentimental timepiece. He was a machinist by trade, but really enjoyed riding before his back surgery the year before he passed away. I bought from my mom in 2019. It had about 33k on it. It has 39k on it now.

https://youtu.be/-Ao-W-9euDM

 

88" "B" ( counterbalanced ) engines from 2000- 2006 would be the easiest

 

There are a few on ebay, one with 10k for 2500$ might be worth looking at.
88b engine is what you want.
First thing to do what ever you get used is open it up and do the upgraded bearings and cam plate upgrade

 

I had seen them. I can buy the crankcase as well for about 600. I was more curious as to what would fit in the frame. I guess the 103 is out of the question.