Sounds to me that you just need a 24V transformer with a higher secondary current rating. 0.45A@24V is only 10VA. I guessing you need at least 50VA (2A) rating.
i think they are rating at 2A or more possable at 4.5A
i did one test with a transformer rate 120vac/ 50va, but when i put the pumps on it
the 24.4va drop down to 8.99va, this transformer its about 1A or less.
i think i need a transformer rate at 3A to 5A 50va.
The VA rating of a transformer is obtained by multiplying its secondary voltage by its secondary current rating, so if you know its current rating VA=Vsec×Isec.
If you know its VA rating and Vsec, then Isec=VA/Vsec
Sounds to me that each pump requires 4.5A, so two require 9A, so the required VA rating of the transformer is at least either 24Vac@9A or 24Vac@216VA.