You should be able to get an F54 for way under $500 and throw your current top end on there. Rod/stroke ratio is nice, but you are not going to be revving to the moon, you aren't going to try to pull 500,000 miles out of it I imagine (even so I'm sure it would do it if you treat it right and keep the valve stem seals etc "maintained"). I just dont see it as enough of a difference really, and ultimately without high RPM the side loading forces are not that much different, but for that little extra you could do it if you wanted, I tend to look at things as performance to price ratio, and $500 for another couple pounds of torque here or there compared to the old setup, and then shaving pistons down (machine work and labor $), just doesn't seem worth it unless you are going "all out."
Shoot, for $500 you could buy a whole donor car with another engine of choice and swap that, or even less.