A&E Elegant Flight Cages
A&E Cage Co.
EntirelyPets
Chewy
Generally on the expensive side, but high-quality, a very nice design, and good size. I really like this one, but it's usually out-of-stock on all of the websites I've looked at.
Kings Cages
Bonka Bird Toys: Playtop 32x23x69
Amazon: Flight Cage
Bonka Bird Toys: Playtop 24x22x63
Listed in order of most to least favorite, generally expensive but the cages are high-quality and have good sizes. Second choice after A&E, since the A&E cages usually seem to be out of stock or temporarily unavailable.
A&E Playtop Cages
PetCo: White 32x23
PetCo: Burgundy 32x23
Being from the A&E Cage Company, these should be high-quality cages. Nice designs, on the expensive side.
Yaheetech Flight Cage
Amazon
Likely the most cheap option, decent quality for the price. Most of the reviews seem to be positive.
Prevue Cages
Amazon: White Dometop
PetSmart: White Playtop
Good sizes and looks nice, but the reviews seem to be mixed. Slightly expensive.
You & Me
PetCo
Slightly expensive. The reviews mostly seem to be positive.