Depending on the boat and size and load??????
The 89 125 came with a 17p or a 19p
Depending on the size boat, it can use as low as a 13p(pontoon) 15p= big boat.
Unless the blades are completely gone?? then the prop can be rebuilt.
About every marine repair has access to a prop shop.
On your prop is a # stamped in the side or on the end where the nut tightens.
Post yours.
If you need there is a prop forum here.
Also Michigan Propeller has a prop service.
Give them the info on the boat, they can recommend the right prop..