Purchase advice needed for Partner

I’m shopping for my girlfriend, and I know a bit about her but I’d like some more insight given in a male.

She has a medium habu that she likes, and is interested in sizing up. She likes a good stretch and the swell of habu, which she is able to hilt. She was looking at an echo horn among others, but not sure on what size.

Also open to other recommendations, but bottom line is she is looking to size up girth wise, and she likes the g spot stimulation from the habu swell.

Thanks guys and gals!

Edit: I should add that we are working up with the idea of her taking my fist.