Bicycle Mechanics - Shimano RSX freehub - 7 speed to 8 speed?

I used the search and couldn't find this question so I'll ask.
I have a '96 Mongoose Omega touring bike equipped with Shimano RSX components. It is 3 x 7 speed, originally using STI shifters. I swapped those out for 8 speed Ultegra bar ends (I'm using them in friction mode with the 7 speed ... works fine) I have an 8 speed cassette that I tried to install to upgrade to 8. I found that the 7 speed freehub would not accommodate the 8 speed cassette (freehub is too narrow) I know that later on RSX came in 8 speed. Does anyone know if I can change to an 8 speed freehub on this hub?

Thanks
Henry

Yes. If you can find the right one.

Based on what I've read (searching Bikeforums using Google) almost any (excluding oddball stuff like Dura Ace and XTR) Shimano freehub will work on any Shimano hub. The cheapest way to acquire a Shimano freehub is to buy a low end Shimano rear hub (Sora, Tiagra) and scavenge the freehub and possible the drive side cone/dust seal as your original might not fit. I've found Tiagra rear hubs as cheap as $20 whereas sellers are asking over $30 for just the freehub.

I appreciate your replies. Good call on the hub instead of trying to find an actual freehub body only. I wasn't sure if the RSX was unique. I might have access to an 8 speed Acera hub. I had no idea it could work. Do you think my wife will notice that her hybrid suddenly has just 7 speeds back there? (she hasn't ridden that bike in a couple of years :))

Thanks again,
Henry

You could always give it a shot with the Acera parts. No harm in trying. If it works, you know what you need to buy to get her bike back together.