Sickle mower - decision - New Holland 451 vs. IH 100

I currently own an IH 100 7 foot sickle bar mower.  Bought it for $500, but need to put 500-700 into in for repairs.

I have the ability to buy a New Holland 451 9 foot mower, including an extra sickle bar.  I think there will be minor repairs necessary.

Both are 3 point.

 

I am thinking about owning both, so I have a backup if I break down.  Which do you recommend?  Will my 1953 Ford Jubilee have enough power to run the 9 foot mower?  I don't plan to have a need to go fast.

 

Thanks

Sickle mower - decision - New Holland 451 vs. IH 100