It's really tough to know how many guys are "walk-ons" because of the limited number of scholarships that are available to the baseball team (11.7 schollies is the max for D-1).. I don't think there are a lot (if any) of full scholarship players on the baseball team, so the vast majority of the guys pay for 50-100% of their college costs.
Closer to half scholarships
Right, they can split the 11.7 scholarships among 30 players, so most guys are getting 1/4 to 1/2 scholarships, with a number of guys getting no assistance.
So nobody really knows exactly how many walk ons are on the team?