Where I work, we can order the beef heart in at a customer's request and dice it into any sized pieces, making sure the customer only gets "the good stuff" 
I just pretend it is a steak I am dicing for a customer
You kind of get used to it after a while.
Anyway, my point is that a lot of butchers will be willing to prepare it for you if you ask nicely Mind you, it is often more expensive than buying the whole beef heart and doing it yourself, although we only charge $5 CAD/ heart (no profit for us).
I just pretend it is a steak I am dicing for a customer
You kind of get used to it after a while.Anyway, my point is that a lot of butchers will be willing to prepare it for you if you ask nicely
Mind you, it is often more expensive than buying the whole beef heart and doing it yourself, although we only charge $5 CAD/ heart (no profit for us).
