You say the "frame" on your's is bent. How so? The tables are typically cast iron, and break rather than bend.
Do you mean the support base? It can be fixed, most likely because it's sheet metal.
The only way to determine if the 9" saw will allow 10" blades is an "In Person" fitting.
A 10" blade is 1/2" larger in radius, so it needs to have no interference at least 1/2" from any metal obstruction inside the base.
The earliest table saws, at least Craftsman and Dunlops were smaller 8" versions, then the radial arms saws followed with 9"blades.
I'm talking in the 1940's. That would mean the 9" is is close to that vintage, so beware!
I doubt any manufacturer makes a 9" saw these days. I donno for certain without researching it.
I would not "go there" if it were me and wait for a proper 10" table saw.
OR fix the bent base on yours!

 

Personally, I wouldn't buy anything made by Rockwell unless it was made in the 20th century. The quality of their equipment has gone to H in the last 25 years. Then their attitude toward their customers couldn't be worse. When they decide to discontinue a machine they don't continue to make parts for it, they empty out their parts inventory to finish production on what they started. You could buy a brand new machine and find out parts for it has been discontinued.

There wouldn't be enough clearance to put a 10" blade on a saw made for 9". You would have to start buying 9" blades.

 

Thanks guys, I'll pass on the 9"

The part that is bent on mine is the rectangular sheet metal box between the cast saw top and the leg/frame. I'll try to remove it from the cast iron and see if I can straighten it out.

I've never liked the metal frame legs and since I want a table saw island in the middle of the shop I think this is the opportunity to build a wooden base.

I'll start a separate thread for that.

 

The part that is bent on mine is the rectangular sheet metal box between the cast saw top and the leg/frame. I'll try to remove it from the cast iron and see if I can straighten it out.

That is what you need to do! If you have a Crescent wrench or Vise grips it may help to bend the flanges.
Without seeing the actual damage it's difficult to give advice, but I have bent a whole lot of metal including making an entire truck body:

Most recently, I made a bottom support for a splayed leg bandsaw stand with too many tricky angles on the edges.:

 

The Rockwell 9" models were designed around 9" blades, and unfortunately you can’t safely run 10" blades on them. The guard, throat plate, and arbor just aren’t set up for it. They were basically marketed as lighter-duty contractor saws back in the day. If you already have a bunch of 10" blades, you’d probably be better off holding out for a 10" saw so everything matches up.