Need advice please.

Hey guys, I have collected cards on and off so I have a reasonable understanding of the hobby but I don’t have much experience with vintage cards or selling.

I have a family member that found a small stack of his old childhood cards. This Mantle is the only higher value card, I believe.

He just retired, is downsizing and could really use the proceeds from the sale of this card.

My question is about how to best approach selling it for him? Should I send it to SGC/PSA or is that an unnecessary expense in this case? To my eye, the centering isn’t great and a couple of the corners aren’t perfect.

I would really appreciate your thoughts and/or advice.