Prop Options For Motorized Foilboard Build

I am new to the forum and look forward to gathering and sharing information!
I am working on a motorized foilboard, I am making most of the components myself but will need to source a propeller. Can anyone tell me where I could get a prop appropriately sized? I have searched eBay and such and the smallest I’ve found is 7.5 inch diameter, with a not very aggressive pitch.
Thank you!