The VG Resource

I'm thinking taking the jump image and the stand image and alternating them would look okay.

Something like that. Edit the arm position of the jump image a bit, so it looks less like... uh... Maryo's signature jump. As for the stand one... I don't think that can work for a walk/run pose. Maybe you should make a new frame. Personally, I can picture this animation turning out similar to Mario's walk/run in SMB, so I'd suggest making Maryo's walk look similar to that.