It's all good so long that's you.
But if you have someone else working on it I would clear this up with them,
if you are thinking of buying your own engine that might work, or it might be
worth it to just pay the mechanic's shortblock $590?
You see, they may or may not make money on the part, they may or may not care
whose engine goes on and then they may or may not care who buys the engine itself,
but if you have a mechanic doing the actual repair I would likely consult with them first.
Yes, long before buying anything...