Re: what size outboard motor is correct?
There is a big range in weight with 23' cc boats...what exact model is it?
Most would probably disagree with me, but I think choosing the lower end of the recommended HP is the best cost/benefit option. You probably know that 1-2 foot waves are rare in big water and it is not very often you will be able to go 3/4 throttle without a knee replacement.
225HP should do the trick (depending on weight...if dry weight is over 2,500 you may want to up that). In any case, a new motor will run you $8,000 to $12,000 depending on stroke and brand.
I am sure the 2-stroke vs 4-stroke will come up (beaten like a dead horse in this forum...just search). I am more than happy with my 2005 90hp 2-stroke and it is not as loud/environmentally unfriendly as most make it out to be...I know it will outrun a 115 4-stroke with my boat having 1 more 200lb person on board. My friend has the exact same boat just a year older and with the 115.